HENNESSY INDUSTRIES COATS 950 User manual

P.O. Box 3002, 1601 J. P. Hennessy Drive, LaVergne, TN USA 37086 615/641-7533 800/688-6359 Manual Part:9111123 03
HENNESSY INDUSTRIES INC. Manufacturer of AMMCO®, COATS®and BADA®Automotive Service Equipment and Tools. Revision: 11/05
Service Manual and
Troubleshooting Guide
950/1025/1050/1055
950 ProRacer
Computer Wheel Balancers
®

ii • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • iii
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Safety Notes . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Servicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
Equipment Needed . . . . . . . . . . . . . . . . . . . . . .1
Voltage & Phase Checking Procedure . . . . . . .2
Preliminary Inspection . . . . . . . . . . . . . . . . . . .3
Functional Checks
Operational Check . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Accuracy Check (Plane Separation) . . . . . . . . . . . .3 - 4
Rotational Check (Use a Hub Centric Wheel) . . . . . . .4
Calibration Procedures
Weight Sensor Calibration . . . . . . . . . . . . . . . . . . . . .4
A & D Arm Calibration (Code 10) . . . . . . . . . . . . . .4 - 5
Stop-On-Top Calibration (Code 20/21) . . . . . . . . . . . .5
*Distance Gauge Tape Placement (Optimize A) . . . . .5
Error Codes . . . . . . . . . . . . . . . . . . . . . . . . .5 - 6
*Function Codes . . . . . . . . . . . . . . . . . . . . . .6 - 7
Troubleshooting Section for Models 950, 1025,
1050, & 1055 Balancers . . . . . . . . . . . . . . .7 - 16
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Fan Motor Does Not Run (Contactor Model) . . . . . . .8
Accuracy Problems (Plane Separation) . . . . . . . . . . . .8
Rotational Problems (Contractor & Motor
Controller Model) . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Repeatability Problems (Contractor & Motor
Controller Model) . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Display Does Not Light (Contactro Model) . . . . . . . .11
Balancer Does Not Cycle (Contactor Model) . . .12 - 13
Balancer Does Not Brake (Contactor Model) . . .14 - 15
A & D Arm Problems . . . . . . . . . . . . . . . . . . . . . . . .16
Checking Procedures
*Bridge Rectifiers . . . . . . . . . . . . . . . . . . . . . . . . . .17
*Optical Encoder (Code 44) . . . . . . . . . . . . . . . . . . .17
*Motor Circuit Testing . . . . . . . . . . . . . . . . . . . . . . .17
*Motor Circuit Diagram . . . . . . . . . . . . . . . . . . . . . .18
*Piezo Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Replacement Procedures Section for Models
950, 1025, 1050, & 1055 Balancers . . . . . .20 - 25
Front Panel/Printed Circuit Board Assembly . . . . . . .20
Contactor Coil Resistance Measurement . . . . . . . . .20
Front Panel/Printed Circuit Board Assembly
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Touch Panel/Aluminum Back Panel and PCB Assembly . . . .20
Hood Magnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Magnetic Hood Switch . . . . . . . . . . . . . . . . . . . . . .21
*Mechanical Hood/Interlock Switch . . . . . . . . . . . . .21
On/Off Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Contactor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Auxiliary Contactor Block . . . . . . . . . . . . . . . . . . . . .22
Bridge Rectifiers . . . . . . . . . . . . . . . . . . . . . . . . . . .22
A & D Arm Assembly . . . . . . . . . . . . . . . . . . . . . . .23
Fan Motor Assembly . . . . . . . . . . . . . . . . . . . . . . . .23
Rotary Shutter . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Optical Encoder Assembly . . . . . . . . . . . . . . . . . . . .23
Drive Motor Assembly . . . . . . . . . . . . . . . . . . . . . . .24
Piezo Assembly . . . . . . . . . . . . . . . . . . . . . . . .24 - 25
Capacitor Assembly . . . . . . . . . . . . . . . . . . . . . . . . .25
Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Signal Harness . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Repair Procedures for the A & D Arm Assembly
A Pulley Removal . . . . . . . . . . . . . . . . . . . . . . . . . .26
A Pulley Installation/Adjustment (Code 10) . . . . . . . .26
A Potentiometer Replacement . . . . . . . . . . . . . . . . .26
D Pulley Removal . . . . . . . . . . . . . . . . . . . . . . . . . .26
D Pulley Installation/Adjustment (Code 10) . . . . . . . .27
D Potentiometer Replacement . . . . . . . . . . . . . . . . .27
*Motor Service Kit Instructions . . . . . . . . . . .28
*950 Pro Racer . . . . . . . . . . . . . . . . . . . . . . . . .28
*950 Pro Racer Wiring Diagram . . . . . . . . . . . . . . . .29
*950 Wiring Diagram (Contactor Style) . . . . .30
*1050 Wiring Diagram (Contactor Style) . . . .31
*Solid State Wiring Diagrams &
Troubleshooting Guides . . . . . . . . . . . . . . . . .32
For units produced after 1/1/98 . . . . . . . . . . . . . . . .32
Mechanical Hood Switches . . . . . . . . . . . . . . . . . . .32
Mechanical Hood Switch Diagram . . . . . . . . . . . . . .33
*1050 Wiring Diagram (Motor Controller
Style/Magnetic Switches) . . . . . . . . . . . . . . . . . . . .34
*1050 Wiring Diagram (Motor Controller
Style/Mechanical Switches) . . . . . . . . . . . . . . . . . . .36
*Motor Controller Test Box #8112708 . . . . . . . . . . .38
*Display Does Not Light (Solid State Motor
Controller Model) . . . . . . . . . . . . . . . . . . . . . . . . . .39
*Balancer Does Not Cycle (Solid State Motor
Controller Model) . . . . . . . . . . . . . . . . . . . . . . . . . .40
*Balancer Does Not Brake (Solid State Motor
Controller Model) . . . . . . . . . . . . . . . . . . . . . . . . . .41
*PCB Checklist Addendum . . . . . . . . . . . . . . .42
Diode Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
IC Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
*Glossary of Terms . . . . . . . . . . . . . . . . . . . . .43
*This manual has been updated to include all related
models. Items that are new are high lighted by an asterick
(*) for your convenience.

iv • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Safety
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
READ ALL INSTRUCTIONS
1. Eye and face protection recommendations:
“Protective eye and face equipment is required to
be used where there is a reasonable probability of
injury that can be prevented by the use of such
equipment.” O.S.H.A. 1910.133(a) Protective gog-
gles, safety glasses, or a face shield must be pro-
vided by the owner and worn by the operator of
the equipment. Care should be taken to see that
all eye and face safety precautions are followed by
the operator. ALWAYS WEAR SAFETY GLASSES.
Everyday glasses only have impact resistant
lenses, they are not safety glasses.
2. Do not disable hood safety interlock system, or in
any way shortcut safety controls and operations.
3. Be sure that wheels are mounted properly, the
hub nut engages the arbor for not less than four
(4) turns, and the hub nut is firmly tightened
before spinning the wheel.
4. Read and understand this manual before operat-
ing. Abuse and misuse will shorten the functional
life.
5. Be sure the balancer is properly connected to the
power supply and electrically grounded.
6. Do not operate equipment with a damaged cord
or if the equipment has been dropped or damaged
– until it has been examined by a qualified serv-
iceman.
7. Do not let cord hang over edge of table, bench, or
counter or come in contact with hot manifolds or
moving fan blades.
8. If an extension cord is necessary, a cord with a
current rating equal to or more than that of the
equipment should be used. Cords rated for less
current than the equipment may overheat. Care
should be taken to arrange the cord so that it will
not be tripped over or pulled.
9. Keep guards and safety features in place and in
working order.
10. Wear proper clothing. Safety toe, non-slip
footwear and protective hair covering to contain
hair is recommended. Do not wear jewelry, loose
clothing, neckties, or gloves when operating the
balancer.
11. Keep work area clean and well lighted. Cluttered
and/or dark areas invite accidents.
12. Avoid dangerous environments. Do not use power
tools or electrical equipment in damp or wet loca-
tions, or expose them to rain.
13. Avoid unintentional starting. Be sure the balancer
is turned off before servicing.
14. Disconnect the balancer before servicing.
15. Use only manufacturer’s recommended acces-
sories. Improper accessories may result in per-
sonal injury or property damage.
16. Repair or replace any part that is damaged or worn
and that may cause unsafe balancer operation. Do
not operate damaged equipment until it has been
examined by a qualified service technician.
17. Never overload or stand on the balancer.
18. Do not allow untrained persons to operate
machinery.
19. To reduce the risk of fire, do not operate equip-
ment in the vicinity of open containers or flamma-
ble liquids (gasoline).
20. Adequate ventilation should be provided when
working on operating internal combustion
engines.
21. Keep hair, loose clothing, fingers, and all parts of
body away from moving parts.
22. Use equipment only as described in this manual.
23. Use only manufacturer’s recommended attach-
ments.

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 1
Introduction
This service manual contains the functional checks,
troubleshooting, adjustment, and part replacement
instructions for COATS®Models 950, 950 Pro Racer,
1025,1050 and 1055 Wheel Balancers. Exploded views,
illustrations, and an indexed parts list facilitate parts
location, ordering, and replacement. All adjustments
and replacements can be rendered with mechanic's or
electrician's tools.
Safety Notes
High voltages, high torque motors, and high speed
rotating wheels are present in coats wheel balancers.
Follow the safety rules below while servicing a bal-
ancer:
1. Disconnect balancer from power source before
starting any part replacement or internal adjustment.
2. Lower guard hood before starting cycle.
3. Do not wear neckties or loose clothing while serv-
icing the balancer.
4. Be aware of hair length. If hair is long, wear it up
under a hat.
5. Mounting cones must be centered in wheel before
tightening. The wheel must be forced up firmly against
the faceplate. The hub nut must be engaged by a mini-
mum of four (4) full threads.Tighten hub nut by rotating
the wheel and striking a spoke of the hub nut with the
heel of the hand. Failure to tighten the hub nut could
result in serious injury.
Servicing
Service should be performed only by COATS®trained
and authorized service personnel. The troubleshooting
and service procedures in this manual are arranged to
allow rapid and thorough service. The steps are prelim-
inary inspection, functional checks, repair of failure,
replacement or adjustment, and functional checks.
Identification of replacement parts required can be
accomplished by using the pictorial breakdown and
index in this manual. It is important that the functional
checks be performed in sequence and the problem iso-
lated prior to attempting any adjustments or replace-
ments. If an adjustment or replacement is made, the
entire functional checks must be performed success-
fully before the balancer can be considered available for
service.
Equipment Needed
1. AC - DC / Volt - Ohm meter.
2. Test Wheel - Domestic 14, 15 or 16-inch diameter
x6- 6 1/2-inch wide steel wheel with a center hole
suitable for mounting with a back cone. A new 70
series tire properly mounted and inflated, balanced to
within 0.05 ounces should be part of this wheel
assembly. The lateral run out of this wheel
should be less than 1/8".
3. Mechanic's and electrician's tools.
4. Thread locking anaerobic (Loctite 242 or equiva-
lent).
5. Retaining compound (Loctite 601 or equivalent).
6. Dial indicator (runout gauge) with magnetic base,
Starret No. 25-431 or equivalent.
7. Modeling Clay.
8. Motor Controller PCB tester (# 8112708)
9. *Membrane Touch Panel Tester (8112929)
Direct Drive

2 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Voltage & Phase Checking
Procedure
1. Unplug the Balancer from the power source.
2. Perform all voltage checks shown in the appropri-
ate diagram and chart at the power receptacle. If one or
all voltage measurements is faulty be sure to check the
status of the circuit breakers that supply the Balancer.
3. Check from one of the power terminals to the
ground terminal to verify a ground is present. The volt-
age measurement should be approximately one half of
the available voltage (i.e. 220V should read 110V). If the
reading is less that one half the available voltage, there
is not a ground present. Normal acceptable deviation is
plus and minus 10%, damage can occur when voltage
or amperage is beyond 10% design specs.
Note: If any faults are found in the above
procedure, it is the responsibility of the
owner. COATS authorized service personnel
are not responsible for wiring within the
building. Consult a licensed electrical con-
tractor for proper installation to local electri-
cal codes. Power outlets must be enclosed
in a floor raceway or overhead drop if pedes-
trian or equipment traffic can damage
power cord.
4. Plug the balancer to a power source.
5. Use an Ohmmeter to check the resistance
between the frame of the Balancer and the building
ground. The resistance should be less than 1 ohm. If
the resistance measurement is greater that one (1)
ohm, check the power plug and frame connection for
proper contact.
Operation with a defective ground circuit
will create a shock hazard for the operator
and could damage the balancer's electron-
ics. Operation with a defective ground cir-
cuit may void warranty.
CAUTION
RED
WHITE
GREEN
GROUND XYZ
BLACK
GREEN
BLACKRED
GROUND A B
THREE PHASE VOLTAGE REQUIREMENTS / INFORMATION
208V/220V/230V 380V 460V
X - Y 195-250 370-420 420-480
X - Z 195-250 370-420 420-480
Y - Z 195-250 370-420 420-480
Plug
Installed Hubbell2421 Hubbell2431
Required Hubbell2420or Hubbell2430or
MatingOutlet Equivalent Equivalent
SINGLE PHASE VOLTAGE
REQUIREMENTS/INFORMATION
208V/220V/230V
A - B 195 - 250
Plug Hubbell
Installed 5466-C
Required Hubbell5462or
MatingOutlet Equivalent

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 3
Preliminary Inspection
1. Check the power supply to the balancer. See the
procedure on page 6.
2. The Balancer should sit on all three (3) legs. Make
sure the legs have not filled with dirt, wheel weights,
or other foreign matter that may prevent a leg from
making contact with the floor.
3. The floor should be a solid flat surface that does
not allow the balancer legs to set into a recess in the
floor or sink into the floor itself.
4. Check the operation of the cooling fan on the drive
motor. The fan should run as soon as the balancer is
powered. If the fan fails to run check the 1A breaker on
the rear of the machine to see if it has tripped. If it has
tripped, reset it. If it will not reset, see FAN MOTOR
DOES NOT RUN.
5. Inspect cones, hub nut, pressure cup(s) , and
threaded stud for damage. Missing cones or acces-
sories should be replaced.
Functional Checks
Operational Check
1. Turn the power switch ON. The display should read
as follows;
A, W, D - _0.0
Weight Display - _.00
Mode - Dynamic
Operator - A (Model 1050 only)
Grams/Ounces - Last Selection
If the display fails to light, see DISPLAY DOES NOT
LIGHT.
2. Mount your test wheel (described in EQUIPMENT
NEEDED. on the balancer.
3. Enter the wheel parameter data.
Note: If this is a Model 950 and the machine
will not accept keypad entries, replace the
keypad. If this does not correct the problem
replace the PCB and put the original keypad
back in.
Note: If this is a Model 1025,1050 or 1055
and you do not get proper wheel parame-
ters from the A & D Arm, see A & D ARM
PROBLEMS.
4. If the balancer is in round off mode, press and hold
the SHIFT key and press ROUND OFF to enter the non-
round off mode.
5. If the balancer is in gram mode, press and hold the
SHIFT key and press GM/OZ key combination to set
the balancer to read in ounces.
6. Install a 4 oz. weight on the outer rim of the test
wheel.
7. Choose the DYNAMIC balancing mode.
8. Lower the guard hood.
9. Push the START button. The machine should now
cycle. If the machine does not cycle, see BALANCER
DOES NOT CYCLE.
10. The balancer should come up to speed, coast for
several revolutions, and then brake to a stop. If the
machine fails to brake and continues to coast, see BAL-
ANCER DOES NOT BRAKE.
11. The balancer should now have weight values and
position lights displayed.
12. Position the wheel so the display for the center
position LED for the outside (right) plane is flashing.
13. Note the position of the 4 oz. weight and the
weight readings for both planes.
14. Perform five (5) spin cycles and note the posi-
tions and weight readings after each spin cycle. The
weight readings should repeat within .2 oz and the
position within ± 1/2 inch. If they do not, see REPEATA-
BILITY PROBLEMS.
Note: If the customer had problems with a
specific wheel assembly only, make sure
there is no water or debris inside the tire.
Accuracy Check (Plane Separation)
1. Remove the 4 oz. weight from the wheel.
2. Fine balance the test wheel to obtain 0.00 (+0.02)
weight readings on both displays. It may be necessary
to use modeling clay to counter balance small imbal-
ances.
3. Place a 4 oz. weight on the outside of the wheel.
4. Press start. The readings for this cycle should be as
follows:
Inner (Left) Plane = 0.00 + 0.20 oz.
Outer (Right) Plane = 4.00 + 0.10 oz.
Outer Position flashing= 4oz. at bottom-dead-center
± 1/2 inch
5. Move the 4 oz. weight to the inside plane. Press
start. The reading should be as follows;
Inner (Left) Plane = 4.00 ± 0.10 oz.
Outer (Right) Plane = 0.00 ± 0.20 oz.
Inner Position flashing = 4oz. at bottom-dead-center
± 1/2 inch
6. If the above results are not achieved check the A,
W, and D dimensions and perform the A & D ARM CAL-
IBRATION and the WEIGHT SENSOR CALIBRATION.
Direct Drive

4 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
7. Check the placement of the distance tape, see the
DISTANCE GAUGE TAPE PLACEMENT PROCEDURE.
8. If specified results are not achieved see ACCU-
RACY PROBLEMS.
Rotational Check (Use a Hub Centric Wheel)
1. Remove the 4oz. weight from the inner rim and
perform a fine balance to obtain 0.00 (+.02) weight
readings on inner and outer plane.
2. Position valve stem at 6 o'clock. Loosen hub nut
just enough to allow the wheel to move. While holding
the faceplate so it cannot turn, rotate the wheel 90
degrees relative to the faceplate. Tighten hub nut.
3. Press START. Weight readings should be 0.30 oz. or less.
4. Repeat steps 2 & 3. At 180 and 270 degrees
weight readings should be .30 oz. or less.
5. If the specified results are not achieved see ROTA-
TIONAL PROBLEMS.
Calibration Procedures
Weight Sensor Calibration
1. Turn the power switch ON.
2. Mount the test wheel to the machine.
3. Enter the wheel parameters.
4. If the machine is in ROUND OFF mode, toggle it
OFF by pressing and holding the SHIFT key and press-
ing ROUND OFF.
5. If the machine is not in ounce mode put it into
ounce mode by pressing and holding the SHIFT key and
pressing GM/OZ.
6. Press and hold the SHIFT key and press CALI-
BRATE to enter the calibration mode. The display
should read CAL 0.
7. Push the START button. The machine should now
cycle. This cycle is referred to as the zero spin cycle.
8. The balancer should come up to speed, coast for
several revolutions, and then brake to a stop.
9. The display should now read CAL 4.
10. Position the wheel so the display for the center
position LED for the outside (right) plane is flashing.
11. Add a 4 ounce weight to the 12 o'clock position
on the outside (right) of the wheel.
12. Push the START button.
13. The outer (right) weight display should read 4.00
± 0.02 oz. and the center position L.E.D. for the outside
(right) plane should be flashing when the weight is at
bottom dead center.
A & D Arm Calibration (Code 10)
1. Press and hold the SHIFT key and press 0. Then
press 1 followed by 0. The A pot reading is displayed on
the left weight display and the D pot reading is dis-
played in the right weight display. The reading for the A
pot should be between 0.05 and 0.30 and the D read-
ing should be between 0.40 and 0.80 when the arm is
in the park position. If the readings are not between the
given values see A and/or D PULLEY INSTALLATION.
2. Rotate the arm to the maximum diameter position.
While holding the arm in this position, press the MODE key.
3. Return the arm to the park position and press the
MODE key.
4. Pull the arm out to the test wheel and position it
into the radius of the wheel. While holding the arm
against the wheel you must enter the "distance" (A
dimension) to the test wheel (enter as 2 digits i.e. 5.8).
Before releasing the arm from this position, enter the
diameter of the wheel (D dimension as 3 digits i. e.

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 5
14.0). After these parameters have been entered, the
weight displays will show 0 and the machine returns to
normal operating mode.
5. Return the arm to the park position. Then pull the
arm out and position into the radius of the wheel. The
correct A and D readings should appear on the wheel
parameter display. These values would be within ± 0.20
of the values entered in calibration. If the readings are
not within tolerance, check for slippage of the pot pul-
leys. If they are tight, see A & D ARM PROBLEMS.
Stop-On-Top Calibration (Code 20/21)
1. If the test wheel is not mounted to the machine,
mount it.
2. Press and hold the SHIFT key and press 0. Then
press 2 followed by 0. This will toggle the machine into
Stop on Top feature. The weight display should now
read SOT ON. If the display now reads SOT OFF, repeat
the key sequence shown above.
3. Add a 4 oz. weight to the outside of the test wheel.
4. Press the START button.
5. When the wheel stops press and hold the SHIFT
key and press 0. Then press 2 followed by 1 to cali-
brate.
6. Repeat steps 4 and 5 until the wheel stops with
the 4 oz. weight at approximately 6 o'clock.
*Distance GaugeTape Placement (Optimize A)
If the ACCURACY CHECK fails, try entering an A dimen-
sion .1 higher than the one used originally. If the plane
separation gets worse, try using an A dimension .1 lower
than the one used originally. If the plane separation gets
better, keep increasing or decreasing the A dimension
until an acceptable value is achieved. Calibrate the
machine and perform the ACCURACY CHECK. Repeat
this procedure until the ACCURACY CHECK produces an
acceptable result. Move the distance tape to the posi-
tion to allow proper A dimension entry. Calibrate the bal-
ancer using the new A dimension.
Error Codes
The following is a list of error codes. When the bal-
ancer is cycled several operating parameters are
checked. If one of these parameters is not within toler-
ance, the machine will generate one of the following
error codes and use the weight reading LEDs to display
the error code. An explanation of these codes and a
troubleshooting procedure follows each code.
Err - Displayed when an entered parameter entered
is not in the acceptable range or not entered.
Err Hod - Displayed when the hood switch is not
closed (the hood is up, the hood switch is bad) when
the machine cycle is started. Try closing the hood if the
machine still gives this error. See WHEEL DOES NOT
SPIN.
Err Hub - Displayed when the machine detects a no
“load” condition on the motor at start up. If there is a
wheel mounted on the arbor, check the mounting of
the wheel to make sure it is not “slipping”. See
REPEATABILITY PROBLEMS.
Err Cal - Displayed when an error has occurred dur-
ing the calibration process. It can be caused by not
placing the calibration weight on the wheel for one or
both spins, or a defective PCB. The code is generated
by equal piezo outputs in consecutive spins.
Err 1 - Displayed when the wheel moves slowly
when the start button is depressed. This can be caused
by a defective motor, defective contactor, motor control
board, or incorrect wiring of either of the previous. See
WHEEL DOES NOT SPIN.
Err 2 - Similar to Err 1, this message is displayed
when the time to reach measurement speed is too
long. This can be caused by a defective motor, defec-
tive contactor, motor control board, or incorrect wiring
of either. See WHEEL DOES NOT SPIN.
Err 3 - Displayed when no encoder pulse is detected
after the start button is pressed (the motor did not
spin). This can be caused by incorrect wiring to the
encoder, contactor, motor control board, motor, PCB, or
safety interlock switch, If the drive motor did not start
see the troubleshooting procedure for WHEEL DOES
NOT SPIN. If the drive motor does begin to spin. See
OPTICAL ENCODER CHECKING PROCEDURE.
Err 4 - Displayed when the machine detects the
wheel rotation in the reverse direction. This can be
caused by incorrect encoder or motor phasing, motor
control board or a bad PCB. See WHEEL DOES NOT
STOP.
Err 5 - This message is displayed when the time to
brake the wheel to a stop at the end of the cycle is too
Direct Drive

6 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
long. This can be caused by a bad contactor, motor con-
trol board or a bad PCB. See WHEEL DOES NOT STOP.
Err 6 - Displayed when there is no power to the
LEDs on the encoder. This can be caused by a defective
encoder or PCB, or improper encoder wiring. See
OPTICAL ENCODER CHECKING PROCEDURE.
Err 7 - Displayed when a time out occurs within the
software. This can be caused by noise interference in
the encoder circuit causing a signal sequencing error.
Check for a defective ground circuit or line filter prob-
lem.
Note:The machine should be on a dedicated
circuit.
Err 8 - Displayed when The most likely cause is noise
interference. Check for a defective encoder cable, or
defective PCB. Check for a defective ground circuit or
line filter problem.
Note:The machine should be on a dedicated
circuit.
Err 9 - This message is displayed when the speed of
the wheel has decreased at too fast a rate. This could
occur if the machine is extremely cold and a small
wheels mounted on the shaft.
Err 10 - This message is displayed when a sequence
error has occurred with the calibration of the A & D
arm. See the A & D ARM CALIBRATION PROCEDURE.
Err 11 - This message is displayed when an unac-
ceptable A dimension was entered during the A & D
arm calibration process. See the A & D ARM CALI-
BRATION PROCEDURE.
Err 12 - This message is displayed when an unac-
ceptable D dimension was entered during the A & D
Arm calibration process. See the A & D ARM CALI-
BRATION PROCEDURE.
Err 13 - This message is displayed when the A pot is
not adjusted properly. See REPAIR PROCEDURES FOR
A & D ARM ASSEMBLY.
Err 14 - This message is displayed when the D pot
is not adjusted properly. See REPAIR PROCEDURES
FOR A & D ARM ASSEMBLY.
Err 15 - *Displayed when the motor has gone over-
speed prior to breaking. This could be caused by a
defective PCB, encoder, contactor or motor control
board, or incorrect wiring of either of the previous.
*Function Codes
The following is a list of function codes with it’s
description. Codes are entered into the balancer by
pressing and holding the SHIFT key and then pressing
and releasing the zero (0) key. At this time CDE will
appear in the left weight display. The two digit code is
then entered and appears in the right weight display.
There is a slight delay after the second digit is entered
at which time the display blanks temporarily and the
code is executed. There is approximately a 10 second
window from the time CDE appears for the operator to
enter the 2 digit code. If the code is not entered in this
time, the code entry routine will automatically be ter-
minated.
10 Calibrate the A & D arm.
20 Toggle stop-on-top ON or OFF.
21 Calibrate stop-on-top.
40 Displays the software revision on the weight dis-
play. The revision letter(s) is/are shown on the left dis-
play and the revision level is shown on the right weight
display.
41 Indicates presence or absence of A & D arm and
stop-on-top hardware as dictated by the electronics. If
there is no jumper connected between pins 15 and 17
on the 18 pin connector in the harness, the left display
will show AR to indicate an A & D arm is present. If
there is a jumper between these pins, the left weight
display will show NAR to indicate the absence of an A
& D arm. An analogous method is used for the stop-on-
top feature. If there is no jumper between pins 16 and
18, the right weight display will show SOT to indicate
the presence of the stop-on-top hardware; otherwise
the display will show NST. It should be noted that the
presence or absence of the arm and stop-on-top is not
detected directly so if the jumpers are improperly
installed, incorrect information will be displayed.
42 Keyboard Test - After the code is entered all dis-
plays will be blank. When a key is pressed the number
of the key or a description of the function is activated
(MODE and SHIFT keys) is displayed on the wheel
parameter display. To exit the test, press and hold the
SHIFT key and press the zero (0) key.
43 Display Test - All display segments are turned on
simultaneously including decimal points and individual
LED's. The test may be terminated by pressing and
holding the SHIFT key and then pressing and releasing
the zero (0) key. If the test is not terminated manually it
will terminated automatically.
44 EncoderTEST - The encoder count is displayed on
the right weight display and the left display is blanked.
The count should be zero (0) when the top-dead-center

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 7
indicators are flashing. As the shaft is rotated forward,
the count should increase. At the point where the bot-
tom-dead-center indicators are flashing, the count
should be 128 and should continue to increase as the
shaft is rotated in the forward direction. The maximum
count should be 255 which occurs just before the top-
dead-indicator begin to flashing as the shaft is being
rotated forward. If the shaft is being rotated in the
reverse direction, the above comments apply to top-
dead-center and bottom-dead-center. The count will
decrease from 255 to zero (0) as the shaft is being
rotated in the reverse direction from top-dead-center.
The test may be terminated by pressing and holding
the SHIFT key and then pressing and releasing the zero
(0) key.
47 Cycle Count - This code displays the cycle count
of the board. The cycle count is displayed in the weight
display. The weight displays are treated as a single 6
digit display when displaying the count.
50 Exit Code - Code to escape from continues loop
such as when displaying the transducer outputs.
51 A & D Arm Adjustment - This code represents a
subset of code 10 (A & D arm calibration). It allow the
A & D potentiometers to be continuously monitored
with out having to do a complete calibration. The pri-
mary purpose is to enable the pulleys to be adjusted on
the potentiometer shaft.The A potentiometer voltage is
displayed on the left weight display and the D poten-
tiometer voltage is displayed on the right weight dis-
play. To exit this code, enter code 50.
52 Piezo OutputTest - 300 RPM. Used to verify that
the output of the piezo are consistence through several
spins. Refer to the checking procedure, piezo output.
53 Piezo OutputTest - 200 RPM. Refer to the check-
ing procedure, piezo output.
99 Counter Reset - This code resets the counter on
the 950, 1025,1050, and 1055.
Troubleshooting Section for
Models 950,1025,1050 & 1055
Balancers
Introduction
For balancers with Solid State Motor Controllers refer
to that section only in the flow charts and wiring dia-
grams located in the back of this manual. The trou-
bleshooting section of this manual makes use of flow
charts. These flow charts will enable you to more
quickly and accurately locate the problem with the bal-
ancer. The main topics covered by these flow charts are
FAN MOTOR DOES NOT RUN, ACCURACY PROB-
LEMS, ROTATIONAL PROBLEMS, REPEATABILITY
PROBLEMS, DISPLAY DOES NOT LIGHT, BALANCER
DOES NOT CYCLE, and BALANCER DOES NOT
BRAKE. These flow charts may refer you to another
section of the manual. If after a repair has been com-
pleted you encounter another or similar problem, refer
to the section that best describes the problem cur-
rently encountered. The flow charts are designed to
lead you to the most likely problems towards the top of
the chart, where possible. Hennessy Industries, Inc.
hopes this manual will help you provide the best and
most thorough service to our customers.
The flow charts will refer to several voltage checks at
various points. To avoid lengthy and confusing charts,
the voltages shown on the blocks of the chart are nom-
inal. To better define these voltages see the range chart
below:
120VAC = 98 to 125VAC
220VAC = 198 to 240VAC
27VDC = 22 to 32VDC
Direct Drive

8 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Did you perform weight
sensor and A - D arm
calibration?
No
Is position accurate?
Perform weight sensor & A - D arm
calibration, see Calibration
Procedures
Check/Replace piezo
sensors. Did this correct
problem?
Return to FUNCTIONAL
CHECKS.
Replace PCB Assembly,
see Replacement
Procedure.
Is weight reading
accurate?
Yes
Yes
Yes
No
No
Yes
No
No
Replace optical encoder.
Check for loose shutter
wheel. Did this correct the
problem?
Yes
Turn the power
switch ON.
Is the power switch set
to the ON position?
No
Yes
See the troubleshooting
procedure,
DISPLAY DOES NOT LIGHT.
Does the display light?
No
Yes
No
Reset the tripped breaker.
Did the breaker trip
again?
Has the 1A breaker for
the fan motor tripped?
Yes
Unplug the machine and disconnect
the fan motor lead from the circuit
breaker and reset the breaker. Plug in
the machine and turn the power switch
ON. Did the circuit breaker trip?
Yes
Is the fan motor
running?
No
Return to FUNCTIONAL
CHECKS..
No
Yes
Replace the circuit breaker,
see Replacement Procedure.
No
Yes
Is there 120VAC between the
terminals marked 0V & 120V
on the transformer?
Replace the transformer see
Replacement Procedure.
No
Yes
Replace the fan motor, see
Replacement Procedure.
Fan Motor Does Not Run (Contactor Model)
Accuracy Problems (Plane Separation)

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 9
Is the test wheel balanced
to 0.00 +.02oz?
Are there burrs, dirt, and/or
grease on faceplate, test wheel,
cones, or pressure cup prevent-
ing perfect centering of the
wheel?
Are there worn or defective
cones, pressure cup, threaded
stud, backcone spring, or hub
nut?
Fine balance test wheel
and test again.
Perform WEIGHT “SENSOR CALIBRA-
TION procedure or refer to “ACCURACY
PROBLEMS”flow chart and test again.
Remove burrs and dirt
and test again.
Replace defective parts
and test again.
Yes
Did the balancer pass the
ACCURACY CHECK?
Yes
Yes
No
No
No
No
Yes
Using a dial indicator check the
runout on the mounting surface of the
motor face plate & the runout of the
arbor shaft. Are both total indicated
runouts greater than .001"?
Yes
Try mounting the wheel with a new
centering cone and spring. Does the
balancer now pass the rotational test?
No
No
Yes
Return to FUNCTIONAL
CHECKS.
Replace drive motor, see
Test again.
Rotational Problems (Contactor & Motor Controller Model)
Direct Drive

10 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Is the hub nut broken or
the cones damaged?
Is the balancer sitting on
a hard flat surface.?
Is the balancer located near a
piece of equipment that
causes the floor to vibrate?
Replace the damaged
part(s).
Move balancer to a another
location in the shop.
Mark the wheel & faceplate with
a piece of chalk and check after
each spin. Is the wheel slipping
against the face plate?
Clean the faceplate and/or remove all
nicks. Make sure wheel is chucked
tightly against faceplate
No
Check the piezo wiring at the
piezo and at the P.C.B. plug for
good connections.
Repair defective
connection(s).
Good
Yes
Replace the drive motor
assembly. See
Replacement Procedure
No
Replace the PCB. See
Replacement Procedure. Did this
correct the problem?
Adjust springs. See step, 19 in
“DRIVE MOTOR REPLACEMENT
PROCEDURE”.
Did this correct the problem?
Yes
Check/replace piezos, see the
procedure on page 32. Did
this correct the problem?
No
Yes
Yes
No
Yes
Yes
No
Bad
No
No
Check/replace the optical
encoder. See the procedure on
page 30 - 31. Did this correct
the problem?
Yes
No
Return to FUNCTIONAL
CHECKS.
Check the tension adjustment on the
motor springs. See step 19 in the
"DRIVE MOTOR REPLACEMENT
PROCEDURE".
Where they adjusted properly?
No
Yes
Repeatability Problems (Contactor & Motor Controller Model)

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 11
Turn the power
switch ON.
Is the power switch set
to the ON position?
Is the proper voltage and ground
present at the receptacle? See
AC CheckingProcedure
No
Yes
Has one of the 3A breakers on
the power panel tripped?
Is there between 200 & 230VAC
between the terminals marked 0V
& 230V on the transformer?
Disconnect the 2 RED wires
from the circuit breakers. Is
there 20VAC between these 2
RED wires? Reconnect wires.
Replace the transformer, See
Replacement Procedure
Turn the power off and unplug the
machine. Check the continuity of
the two (2) 3A circuit breakers.
If either of the breakers are open,
try resetting and rechecking. If
the breaker remains open & does
not trip, replace the breaker.
Connect the machine to a power
source and turn the power switch
ON. Is there 20VAC between
pins 1 & 2 on the connector on
the right side of the PCB?
Turn the power off and unplug
the machine. Turn the power
switch to the ON position. Check
the continuity of the wire from the
230V terminal on the transformer
to terminal 4 (950) or terminal 64
(1050) on the forward contactor.
Is there 220VAC between
terminals 4 & 6 on the
forward contactor?
Is there 220VAC between
terminals 4 & 6 on the
brake contactor?
Yes
Yes
No
Yes
No
No
Check the continuity of the
power cord from the terminals to
the appropriate connection on
the brake contactor.
Repair or replace
the defective wire
or connection.
Checks
Bad
Checks Good Breaker
Trips
Checks
Bad
Yes
No
Yes
No
No
No
Yes
Have the voltage supply
to the machine
corrected.
Replace or repair the defec-
tive jumper wire from the
forward to brake contactor.
Replace the PCB. See
Replacement Procedure
Reset the tripped breaker. If the
breaker trips again, replace the PCB.
See Replacement Procedure
Yes
Turn the power off and unplug the
machine. Check the continuity of
the RED wires from the trans-
former pins 1 & 2 on the connec-
tor on the right side of the PCB.
Checks
Good
Repair or replace the
defective wire or connection.
Checks
Bad
Check the continuity of the wire
from the terminal marked 0V on
the transformer to terminal 6 on
the forward contactor.
Checks
Good
Checks
Bad
Replace the power switch, See
Replacement Procedure
Check the continuity of
the power switch.
Checks Bad
Checks Bad
Checks
Good
Direct Drive
Display Does Not Light (Contactor Model)

12 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Reset the breaker &
press the start button. Proceed to balance.
Does the forward contactor
close when the start button
is depressed?
Will the balancer cycle with
both the hood switch wires
on the same terminal? Replace the hood switch
Replace the transformer. See
Replace Procedure.
Is there 27VAC between the two
orange wires on the transformer?
Replace the contactor. See
Replace Procedure.
Correct the voltage
supply to the machine.
Is the proper voltage and
ground present at the
receptacle? See page 6 for
the checking procedure.
Has one of the 1A circuit
breakers on the rear of the
machine tripped?
Yes
No
Does Not
Trip
Trips
Yes
No Yes
No
Yes
No
No
Yes
CONTINUED ON NEXT PAGE
Is there 230VAC on terminals 4
to 6, 6 to 14, & 14 to 4 on the
brake contactor?
Repair or replace defective
power cord or connections.
Is there 230VAC on terminals 4 to
6, 6 to 14, & 14 to 4 on the
forward contactor?
Repair or replace defective
jumper wire or connections.
No
Yes
Yes
No
Voltage
Present
Replace the contactor.
See Replace
Procedure.
Does Not Trip
Turn the power switch OFF and unplug the machine.
Disconnect the white/violet wire from the forward
contactor, reset the breaker. Plug in the machine,
turn the power switch ON, & press the start button.
Replace the PCB.
See Replace
Procedure.
Trips
*Manually close the forward
contactor & check for 230 VAC on
terminals 3 to 5, 5 to 13, & 13 to 3
of the forward contactor?
Voltage Not
Present
Turn the power switch OFF and unplug
the machine. Disconnect the connector
from the right side of the PCB. Is there
continuity between A2 of each contactor?
Is there continuity from A1 of
the forward contactor to
terminal 6 of the connector on
the right side of the PCB?
Yes
Is there 3 to 5 or (5 to 7 new
contactors)Ohms resistance
between A1 & A2 on the
forward contactor?
Yes
No
Yes
Replace the PCB.
See Replace
Procedure.
No
Balancer Does Not Cycle (Contactor Model)
To use the following chart you will need a tire and wheel assembly mounted on the balancer, the hood closed,
and the proper A, W, and D dimensions entered. If you are unable to manually enter the proper wheel dimensions,
replace the touch panel.
Manually closing the contactor
to check voltage may cause the
wheel to spin at high speeds.To
avoid this from happening dis-
connect the wires going from
the contactor to the motor.
CAUTION

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 13
CONTINUED FROM
LAST PAGE
Is there 230VAC from terminals
64 to 74, 74 to 84,& 84 to 64 on
the forward contactor?
Repair or replace defective
jumper wire or connections.
*Manually close the forward contac-
tor & check for 230VAC on terminals
63 to 73, 73 to 83, & 83 to 63 of the
forward contactor.
Manually close the forward
contactor. Use an Ohmmeter to
check from terminal 2 to terminal 1
on the forward contactor.
Use an Ohmmeter to check from
terminal 74 on the brake contactor to
terminal 2 on the forward contactor.
Yes
No
Voltage Present
Less Than 1 Ohm
Less Than 1 Ohm
Replace the contactor.
See Replace Proce-
dure.
Less Than 1 Ohm
More Than
1 Ohm
More Than
1 Ohm
More Than
1 Ohm
Voltage
Not
Present
Replace the forward
auxiliary contactor. See
Replace Procedure.
Repair or replace
defective jumper wire
or connections.
Turn the power switch OFF & unplug
the machine. Use an Ohmmeter to
check from terminal 53 on the
forward contactor to terminal 74 on
the brake contactor.
Is this a Model 1050.
No
Yes
If this is a single phase unit try
repalcing the capicator assy.,
See Replace Procedure.
After verifying the integrity of
the motor connections at the
contactor. Replace defective
motor assembly. See
Replace Procedure.
Motor Does
Not Run
Repair or replace defective
jumper wire or connections.
Is this a Model 950.
Yes
*Manually close the forward
contactor. Is there 230 VAC on
terminals 3 to 5, 5 to 13, & 13 to 3
on the forward contactor?
Yes
No
Check connections at the wire
nut where the three motor
wires are joined.
Repair or replace
defective connection.
Bad
Connection
GoodConnection
If this is a single phase unit try
replacing the capicator assy.,
See Replace Procedure.
After verifying the integrity of
the motor connections at the
contactor. Replace defective
motor assembly. See
Replace Procedure.
Motor Does
Not Run
Direct Drive
Manually closing the contactor to check voltage may cause the
wheel to spin at high speeds.To avoid this from happening dis-
connect the wires going from the contactor to the motor.
CAUTION

14 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Does the wheel rotate clockwise
when the forward contactor is
engaged Reverse any two power leads
at power source and re-test.
Does the brake contactor
remain closed?
Turn the power switch OFF &
unplug the machine. Disconnect
the white/blue wire from A1 on the
brake contactor. Use an Ohmme-
ter to check from A2 on the brake
contactor to terminal A2 on the
forward contactor. Connect the
white/blue wire.
Has one of the 1A breakers on
the rear of the machine tripped?
Disconnect the wire from terminal A2
of the brake contactor & check the coil
resistance from A1 - A2. Is the
resistance of the coil between 3 & 5
Ohms (5 to 7 on new contactors)?
Is there 27VAC between A2 on
the brake contactor & terminal 4
on the connector on the right
side of the PCB?
Does the brake contac-
tor ever close?
No
Yes
No
Replace the optical encoder.
See Replace Procedure.
No
Yes
No
Yes
Replace the PCB. See
Replace Procedure.
Disconnect the wire from A2 on
the brake contactor. Use an
Ohmmeter to check continuity
from A1 on the brake contactor to
terminal 5 on the connector on
the right side of the PCB.
Connect the wire to terminal A2
on the contactor.
Replace the PCB. See
Replace Procedure.
No
Yes
No
Yes
Less Than 1 Ohm
Repair or replace
defective wire or
connection.
More Than
1 Ohm
More Than
1 Ohm
Less
Than 1
Ohm
Yes
Replace the contactor. See
Replace Procedure.
Manually close the brake
contactor. Is there a 230VAC
between terminals 3 to 5, 5 to
13, & 13 to 3 ?
Is this a Model 950?Replace the contactor. See
Replace Procedure.
Yes
No
No
Yes
CONTINUED ON
NEXT PAGE
Check the connections from
the contactor to the motor. Repair or replace the defec- tive wire or connections.
Bad
Good
Replace the drive motor. See
Replace Procedure.
Replace the optical encoder.
See Replace Procedure.
Does the forward
contactor ever open?
No
Yes
Balancer Does Not Brake (Contactor Model)
Manually closing the contactor to
check voltage may cause the wheel to
spin at high speeds. To avoid this from
happening disconnect the wires going
from the contactor to the motor.
CAUTION

Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055 • 15
Does the Balancer trip a circuit
breaker on the electrical panel
when it starts the brake cycle?
CONTINUED FROM
LAST PAGE
Manually close the brake
contactor. Is there 220VDC on
between terminals 13 & 54 on
the forward contactor?
Manually close the brake
contactor. Is there 220VAC
between terminals 3 & 5 on
the lower contactor?
Check the bridge rectifiers.
See Checking Procedure.
Turn the power switch OFF and unplug
the balancer from the power source.
Manually close the brake contactor. Use
an Ohmmeter to check between termi-
nals 53 & 54 and between terminals 83
and 84 on the brake contactor. Is there
less than 1 Ohm on both checks?
Replace the auxiliary
brake contactor. See
Replacement Procedure.
Turn the power switch OFF. Manually close the brake contac-
tor. Use an Ohmmeter to check these connections for conti-
nuity on the brake contactor, 63 to 64 & 73 to 74. If your meter
fails to read 0.0 ohms, replace the auxiliary (piggy back)
contactoronthebrake contactor. While thecontactorisclosed
alsocheckterminals1to2onthebrakecontactor. Ifyourmeter
fails to register any resistance, replace the primary contactor.
Use an Ohmmeter to check the following connections. If your
meter fails to register 0.0 ohms, repair or replace the defective
wireorconnection(s)associatedwiththeterminalsjustchecked.
Forward contactor terminal 1 to brake contactor terminal 2.
Forward contactor terminal 5 to brake contactor terminal 1.
Forward contactor terminal 3 to brake contactor terminal 63.
Forward contactor terminal 73 to brake contactor terminal 64.
Forward contactor terminal 53 to brake contactor terminal 74.
Forward contactor terminal 83 to brake contactor terminal 73.
Yes
No
Yes
No No
Yes
No
Yes
Replace the contactor. See
Replace Procedure.
After verifying the integrity of
the motor connections to the
contactor, replace the motor
assembly. See Replacement
Procedure.
Use an Ohmmeter to check for continuity on the following
connections. If your meter fails to register any resistance,
repair or replace the defective wire or connection(s) associ-
ated with the terminals just checked.
Forward contactor terminal 13 to brake contactor terminal 84.
Forward contactor terminal 54 to brake contactor terminal 54.
Brake contactor terminal 83 to both rectifiers terminal “+”.
Brake contactor terminal 53 to both rectifiers terminal “-”.
Brake contactor terminal 5 to all 4 rectifier terminals “~”.
(Only one terminal on each contactor will give a reading.)
Brake contactor terminal 13 to 2 rectifier terminals “~”that did
not render a reading in the previous check.
Direct Drive
Manually closing the contactor to check voltage
may cause the wheel to spin at high speeds. To
avoid this from happening disconnect the wires
going from the contactor to the motor.
CAUTION

16 • Service Manual — COATS Models 950/950 ProRacer/1025/1050/1055
Direct Drive
Has the arm returned all
the way to the bushing?
Does the balancer accept
entry from the A - D Arm?
Replace the PCB. See
Replacement Procedure.
Does the “A”dimension
entered by the A-D arm
match the distance shown
on the Distance Tape?
Does the “D”dimension
entered by the A-D Arm
match the diameter
shown on the tire?
Proceed to balance.
No
Yes
No
No
Yes
Yes
Power cycle the
machine, does the
Balancer “Beep”
for 20 seconds?
No
No
Yes
Return the arm to the
“Home”position. The end of
the arm should be resting
against the guide bushing.
Power cycle the machine.
Calibrate the A - D Arm, See
Calibration Procedure.
No
Yes
Does the balancer hold the
initial “A”& “D”dimensions?
Key “Shift + 0, 1, 0”.
Does the potentiometer
for “A”(left weight display)
reading between .05 and
.30 & the “D”(right weight
display) reading between
0.4 and 0.8?
Yes
Yes
Yes
No
Adjust the A - D Arm. See the
“A”& “D”Pulley installation
procedures.
AdjustmentsCompleted
Check the A-D Arm for proper
placement of the Distance Tape.
See DISTANCE GAUGE TAPE
PLACEMENT.
No
A & D Arm Problems