HoldPeak 6688D User manual

AUTOMOTIVE MULTIMETER
INSTRUCTION MANUAL

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6688D
6000 DIGITAL AUTOMOTIVE ENGING
ANALYZER MULTIMETER
OPERATION MANUAL
This instrument is a compact 、battery operated、handheld with safety
protector 、streamline 、6000 digital automotive engine analyzer multimeter for
measuring DC/AC Voltage, DC/ AC Current, Resistance, , Capacitance,
Frequency and Duty cycle, Temperature, Diode/Continuity test, Tachometer,
Dwell .ms-PULSE,Analog Frequency/Duty/Voltage/Resistance Signal Output ,It
is an ideal instrument for all drivers.
Safety
DANGER
Engines produce carbon monoxide which is odorless, causes slower reaction
time .and can lead to serious injury .when the engine is operating keep service
areas WELL VENTILATED or attach the vehicle exhaust system to the shop
exhaust removal system.
Set the parking brake and block the wheels before testing or repairing the
vehicle .it is especially important to block the wheels on front-wheel drive
vehicles: The parking brake dose not hold the drive wheels.
Wear an eye shield when testing or repairing vehicles .exceeding the limits of
this meter is dangerous, it will expose you to serious or possibly fatal
injury .carefully read and understand the cautions and the specification limits of
this meter.
Voltage between any terminal and ground must not exceed 1000V DC or 750V
AC.
Use caution when measuring voltage above 25VAC or DC.
Circuit tested must be protested by a 20A fuse or circuit breaker.
Do not use the meter if it has been damaged
Do not use the test leads if the insulation is damaged or metal is exposed .
Use current clamps tomeasure circuits exceeding 20A.
Danger
Avoid electrical shock : do not touch the test leads ,tips or the circuit being
tested.
Do not try a voltage measurement with the test leads in the 20A or the mA
terminal.
*When testing for the presence of voltage or current . make sure the meter is
function correctly ,take a reading of a known voltage or current before accepting
a zero reading.
*Choose the proper range and function for the measurement . do not try voltage
or current measurements that may exceed the ratings marked on the
function/range switch or terminal.
*When measuring current. Connect the meter in series with the load.
*Never connect more than one set of test leads to the meter.
*Disconnect the live test lead before disconnecting the common test lead.
*The mA and the 20A terminals are protected by fuses . to avoid possible injury
or damage . use only in ciruits limited to 600mA or 20A continuous for 15
seconds .
See also
Fuse Replacement
IMPORTANT
*To maintain accuracy of the meter , replace the discharged battery immediately
when the battery symbol appears on the meter display .
*Avoid measuring error form outside interference : keep the meter away form
spark plug or coll wires .
*Avoid damaging the meter when testing voltage : disconnect the test leads
from the test points before changing functions.
*Do not exceed the limits shown in the table below:
Function
Terminal
Input Limit
AC Volts
V/Ω/RPM
750V AC rms
DC Volts
1000V DC
Frequency
V/Ω/RPM
250V AC/DC
Ohm (resistance)
Diode

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AC/DC 600mA
mA
600mA AC/DC
AC/DC 20A
20A
20A AC/DC
RPM
V/Ω/RPM
250V AC/DC
Duty Cycle(%)
Dwell angle
20Amp measurement continuous for 30 seconds maximum.
Ohm can not be measured if voltage is present ,ohms can be measured only in
a non-powered circuit .however ,the meter is protected to 250 volts.
SPECIFICATION
GENERAL SPECIFICATION
Display: 6000 digits LCD with 20mm high numerals.
Auto Functions: Auto-zero, Auto-polarity, Auto-range
Auto power off: 15 minutes after stopping the switch
or no push button, the meter enter to Power off mode. run switch to OFF
position , Auto Power off disable.
Low Battery Indication: " ".
.Overrange Indication: "OL".
Power Supply: single 9V battery (NEDA 1604or IEC 6F22)
Reading Rate Time: 3 reading per sec(approx.).
Maximum Commom Mode Voltage: 500Vdc or ac peak.
Safety Standards: The meter is up to the standards Of IEC1010
Double Insulation, Pollution degree 2 Overvoltage Category Ⅱ.
Operating Environment: 0℃to 50℃(32℉to 122℉)at ≤70% relative
humidity.
Storage Envrionment: -20℃to 60℃(-4℉to 140℉) at ≤80% relative
humidity .
Temperature Coefficient: 0.1×(specified accuracy)/℃(≤18℃or≥28℃)
Accessories: One pair test leads, single 9V battery (NEDA 1604or IEC
6F22), operating instructions.
Fuse: 0.8A/250V, 5×20mm fast acting,20A/250V, 6×30mm fast acting.
Dimension : 218mm×122mm×75mm
Weight :Approx. 760g(including battery and holster).
Electrical specifications
*Accuracy is given as ±([% of reading]+[ number of leads significant digits]) at
18℃to 28℃(65℉to 83℉),with relative humidity up to 70%.
RPM(tach)
Ranges:60-9000,600-12000(×10RPM)
Resolution :1 RPM
Effect reading :>60RPM
Accuracy:±(2.5%rdg+10dgt)
Overload protection:250VDC or RMS AC
Pulse width
Ranges :0.1ms-10.0ms
Accuracy :±(2.5%+0.2ms)
Overload protection:250VDC or RMS AC
% Duty cycle
ranges:1.0-99.0%
resolution:0.1%
pulse width :>100us,<100ms
Accuracy:±(2.5%rdg+10dgt)
Overload protection:250VDC or RMS AC
Dwell angle
No.of cylinder:4.5.6.8
Range:0-90.0゜(4 cyl),0-72.0゜(5CYL),0-60.0゜(6CYL),0-45.0゜(8CYL.)
Resolution:0.1゜
Accuracy:±(2.5%rdg+10dgt)
Overload protection:250VDC or RMS AC
Temperature
Ranges:-30℃to 1100℃,-22℉to 2000℉
Resolution:1℃/1℉
Accuracy:±(2%rdg+2℃)
±(2%rdg+4℉)
sensor: type K thermocouple
input protection:250VDC or 250VAC rms
DC voltage(auto rangeing)
Ranges:600mV
Accuracy:±(2.5%rdg+15dgt)
Ranges:6V,60V,600V,1000V
Accuracy:±(0.8%rdg+8dgt)
Resolution:100uV
input impedance:>10MΩ
Overload protection: 1000VDC or 750VAC rms.

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AC VOLTAGE TRUE RMS(Auto ranging)
Ranges:600mV,6V,60V,600V,750V
Resolution:100uV
Accuracy: : 400mV ,750V±(3.0%rdg+15dgt) at 50Hz to 100Hz
,4V,40V,400V, ±(1.5%rdg+15dgt) at 50Hz to 1kHz
input impedance:>10MΩ
Overload protection: 1000VDC or 750VAC rms.
DC CURRENT
Ranges: 60mA,600mA,20A.
Resolution:10 uA
Accuracy:
60mA,600mA ±(1.5%rdg+10dgt)
20A ±(2.0%rdg+15dgt)
Input protection: 0.8A/250V fuse on 600mA range
20A/250V high energy fuse on 20Arange
AC CURRENT
Ranges: 60mA,600mA,20A.
Resolution:10uA
Frequency response:50Hz to 400Hz
Accuracy:
60mA,600mA ±(1.8%rdg+15dgt)
20A ±(2.5%rdg+15dgt)
Input protection: 0.8A/250V fuse on 600mA range
20A/250V high energy fuse on 20Arange
RESISTANCE(Auto ranging)
Ranges:600Ω,6KΩ,60KΩ,600KΩ,6MΩ,60MΩ
Accuracy:±(1.5%rdg+15dgts) on 600Ωrange
±(1.0%rdg+10dgts) on 6kΩto 600kΩranges
±(3.5%rdg+15dgts) on 6MΩto 60MΩranges
open circuit voltage: 0.4VDC
overload prctection: 250VDC or RMS AC.
FREQUENCY(Auto ranging)
Ranges: 9.999kHz,99.99kHz,999.9kHz,9.999MHz
Resolution: 1Hz
Accuracy: ±(0.1%rdg+5dgts)
Sensitivity:1V
Overload protection:250VDC or RMS AC
CAPACITANCE(Auto ranging)
Ranges:9.999nF,99.99nF,999.9nF,9.999uF,99.99uF,999.9uF,9.999mF,99.99mF.
Resolution:1pF
Accuracy:±(3.0%rdg+20dgts) on 9.999nF range
±(2.5%rdg+10dgts) on 99.99nF to 9.999uF ranges
±(3.0%rdg+25dgts) on 99.99uF to999.9uF ranges
±(10%rdg+15dgts) on 9.999mF to99.99mF ranges
overload protection:250VDC or RMS AC
DIODE TEST
Test condition: Forward DC current approx. 1.5mA
Reversed DC voltage approx. 1.5V
Overload protection:250VDC or RMS AC.
AUDIBLE CONTINUITY
Open circuit voltage:0.4Vdc
≤50ΩBuzzer sounds
Overload protectio n:250VDC or RMSAC.
Signal analog Output(Analog Frequency/Duty/DC and AC
Voltage/RESISTANCE Signal Output)
% Duty cycle:10%-90%
DC VOLTAGE:0-1V、0-5V、0-12V(±1%)
AC VOLTAGE: 0-1V、0-5V、0-12V(±1.5%)
RESISTANCE:
200-5KΩ±3.5％±0.05 KΩ
4KΩ-200KΩ±3.5％±0.5 KΩ
“︽”“︾”Button quickly adjust output signal value
“∧”“∨”Button fine adjust output signal value
Accessory optional
1. RPM INDUCTIVE PICK-UP PROBE

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Getting Started
This chapter will help you get started.
It describes the basic functions of the meter.
Front Panel
①AC/DC & switch
②Hold switch
③MAX/MIN switch
④PEAK HOLD switch
⑤Back Light switch
⑥RANGE & STROKE 4/2(DIS) & #CYL TRIG±& DC OUTPUT/ Square
wave output
⑦Function/Range switch: Turn this switch to select a function or turn the
meter OFF.
⑧Safety protector
9)Test lead terminal: The Black test lead is used in the Com terminal for all
test . The red test lead is used to measureAmps or Volts
temperature Terminal: insert the temperature probe in this terminal.
Function and e select
Turn the rotary switch in either direction to select a function.
The range is automatically selected by the meter. But you can also select a
range within a function by pressing by pressing the range button.
Always select a range higher than you expect the function . then select a lower
range if better accuracy is needed
*if the range is too high ,the reading are less accurate.
*if the range is too low ,the meter shows OL(over limit)
Push-button Functions
DC/AC BUTTON
Press this button to select the following functions:
DC/AC Voltage & Current Diode/Continuity.
RANGE & Stroke 4/2(DIS)
#CYL TRIGGER ±BUTTON
Press this button to select:
RPM ×10RPM position STROKE4 2 DIS
DWELL position 4CYL 5CYL 6CYL 8CYL
ms-PULSE %DUTY position TRIGGER+ TRIGGGER-
Signal Output DC output / Square wave output
V/A Resistance position Manual Range
MANUAL RANGING
The meter turns on in the autoranging mode. Press the Range button to go to
manual ranging. The display icon " " will appear. Each press of the range
button will step to the next range as indicated by the units and decimal point
location. Press and hold the Range button for two seconds to return to
autoranging.
NOTE:
*If the range is too high .the readings are less aceurate.
*If the range is too low . the meter shows OL(over limit)
Date Hold
The Date Hold feature stores the last reading in memory
*Press the HOLD button once to hold the present reading.
*Press the HOLD button again to exit and resume readings.
max/min button
Press the MAX/MIN button to activate the MAX/MIN recording mode. The
display icon "MAX or MIN" will appear. The meter will go to manual ranging &
display and hold the maximum or minimum reading and will update only when a

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new “max or min” occurs.
4.5.2. Press the MAX/MIN key and a blinking “MAX MIN” will appear. The meter
will display the present reading, but will continue to update and store the max
and min readings.
To exit MAX/MINmode press and hold the MAX/MIN key for 2 seconds.
PeakHold button
The Peak Hold function captures the peak AC voltage or current.
The meter can capture negative or positive peaks as fast as
1 millisecond in duration.
1. Turn the function switch to the A or V position.
2. Press the PEAK button, “Peak MAX” will display.
3. The display will update each time a higher positive peak occurs.
4. Press the PEAK button again, “Peak MIN” will display. The display will now
update and indicate the lowest negative peak.
5. To return to normal operation, press and hold the PEAK button until the Peak
MIN or “Peak MAX” indicator switches off.
Backligh button
1. Press the BACKLIGHT button to turn the backlighting ON.
2. Press the BACKLIGHTbutton again to turn the backlighting OFF.
Meter functions
1. Voltage(V)
The meter will automatically select the best voltage(V) range.
Press “AC/DC”button to select AC or DC.
Insert:
*black lead in COM terminal.
*red lead in V/Ω/RPM terminal .
Touch the Black probe to the circuit coming from the power source.
Touch the Red probe to the circuit coming from the power source .
IMPORTANT: voltage must be measured in parallel (red probe measuring
circuit from power source).
Accuracy
Selection of a lower range will move the decimal point one place and
increase the accuracy of the reading .An OL(Over limit) display means the
range is too low .select the next higher range.
2. Resistance(Ω)
IMPORTANT: if you are testing an application that has capacitors in the circuit.
be sure to turn the power OFF on the test circuit and discharge all capacitors.
Accurate measurement is not possible if external or residual voltage is present.
Select the resistance (Ω) setting with the
rotary switch.
Select the resistance (Ω) range with the
button labeled “RANGE ”if a more
accurate measurement is desired.
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Touch the test lead probes across the
resistor to be tested.
3. Audible Continuity
IMPORTANT: Turn the power OFF on the test circuit
Select the range with the rotary
switch .
Press “ ” button to select Audible
continuity.
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Connect one test probe to each end of
the circuit to be tested.
*circuit complete. The meter will “beep

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*circuit open ,these is no “beep”and the display shows “OL”
4. Diode check
IMPORTANT: Turn the power off to the test circult
Select the range with the rotary switch .
Press “ ” button to select the diode Check( ).
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Touch the Black test probe to the negative(-) side of the diode.
Touch the Red test probes to the positive (+) side of the diode.
Reverse the probes : Black to the positive(+) side and Red to the negative(-)
side.
NOTE:
A ”good ”diode will read low in one direction and high in the other direction
when the probes are reversed (or vice versa).
A defective diode will have the same reading in both directions or read between
1.0 to 3.6V in both directions .
5. Capacitance
IMPORTANT: turn the power OFF
to the vehicle circuit to be tested.
Discharge the capacitor leads
together.Use the DC volts
function to confirm that the
capacitor is discharge.
Select the CAP range with the
rotary switch.
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
NOTE:
*Holding the probes with your hands may charge the capacitance in circuit and
generate a false reading.
*Residual voltage charges on the capacitor. poor insulation resistance or poor
dielectric absorption may cause measurement errors.
6.temperature (Temp)
IMPORTANT: to avoid heat damage to the meter , keep it away from
sources of very high temperature. The life of the temperature probe is
also reduced when subjected to very high temperature (operating range is
-50℉to 2,000℉).
Select the ℃or ℉. setting with the
rotary switch.
Insert the temperature probe
connector into the COM and V/Ω/RPM
socket.
Touch the end of the temperature
sensor to the area or surface of the
object to be measured.
7. Frequency (Hz) Select the frequency (Hz)
setting with the rotary switch . I
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Connect the Black test probe to
ground.
Connect the Red test probe to
“signal out”Wire of the sensor
to be tested.
8. RPM/X10RPM

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Select the RPM range with the rotary switch.
OR select the X10RPM range with rotary switch(60 to 12,000RPM). Multiply the
displayed reading times ten to get actual RPM.
Insert the induction pick-up connecting
terminal into the meter.
*Ground lead in COM terminal.
*output lead in V/Ω/RPM terminal.
Connect the inductive pick-up to a spark
plug wire . if no reading is received ,
unhook the clamp, turn it over and
connect again.
Press the “STROKE 4/2DIS”button to Select cycle/Distributorless lgnition
system (DIS) or RPM 2 for 4 –Cycle engines.
NOTE:
*Position the inductive pick-up as far away from the distributor and the exhaust
manifold as possible.
*Position the inductive pick-up to within six inches of the spark plug or move it to
another plug wire if no reading or an erratic reading is received.
9. Duty Cycle (%)
Select the % Duty Cycle range with the rotary switch .
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Connect the Black test probe to
ground .
Connect the Red test probe to the
signal wire circuit.
10. ms- PULSE (Pules width)
Select the ms pulse range with the rotary switch.
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Connect the Black test probe to
ground.
Connect the Red test probe to the
signal wire that connects to the
component to be measured.
11. Dwell
Select the Dwell range with the rotary switch .
Insert:
*Black lead in COM terminal.
*Red lead in V/Ω/RPM terminal.
Connect the Black test probe to
ground .
Connect the Red test probe to the
signal wire that connects to the
breaker points.
Meter functions –AC or DC current (A)
Select the 10A or mA range with the rotary switch .

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Press the “AC/DC”function button to selectAC or DC.
Insert: *Black lead in COM terminal.
*Red lead in the 10Aor mA terminal.
IMPORTANT:
Turn OFF all power to the circuit or
disconnect the circult from the power
source.
Connect:
*the Red probe to the side of the circuit
closest to the power source.
*the Black probe to the side of the circuit to
ground .
*Turn the power ON and test .
NOTE :
Current must always be measured with the meter test probes connected in
series as described .
.MAINTENANCE
(1) The multimeter is a precision electronic device . Do not tamper with the
circuity . to avoid damage :
A : Never connect a source of voltage under the condition of resistance
measurement .
B : Never operate the meter unless the cover is in place and fully closed .
C : Battery replacement should be done after the test leads have been
disconnected and POWER IS OFF .
(2) turn off the power if the meter is not in use , removed the battery if the
meter will be free for long period .
(3) If a sign “ ” appear on the display , open the compartment cover ,
remove the spent battery and replace it with a battery of the same type .
(4) Contact with the maintenance service center of our company if you have
trouble .
Basic Diagnostic Testing
This chapter leads you through a systematic series of tests that check the
vehicle electrical system . These tests should de performed before testing
individual components.
Electrical System Diagnostics
It is important to diagnose a vehicle electrical problem thoroughly and
efficiently .
The series of tests that follow check primary areas that are responsible for the
majority of the electrical problems found in an automobile . perform these basic
tests,even if a vehicle has a trouble code set in the computer .A component
malfunction detected by the computer can be caused by a basic ground
problem in the electrical system . simply replacing a failed component will not fix
the problem if a poor ground caused the component failure .
The tests begin by checking the main source of power and the chassis ground
circuit connections . Ground circuits are one of the least understood but
potentially most troublesome areas of automotive electronics . An excessive
voltage ground in a circuit effects the entire electrical circuit . this is why it is
important to make sure the basic circuit are in good shape before checking
trouble codes and components.
Battery Testing
[1]Battery Test (surface Discharge)
NOTE:
*Remove the positive and negative battery cables and thoroughly clean the
cable terminals and the battery
posts . Reassemble and begin
testing.
*The ignition switch must be OFF
to prevent damaging the vehicle
computer when connecting or
disconnecting battery cables.
This test checks for a low current
discharge across the battery
case.
*Set the rotary switch to voltage.
*connect the negative (-) lead to
the negative battery post.

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*Touch the positive(+)lead to the battery case around the positive (+) battery
post ,Do not touch the post .
A reading of more than 0.5V indicates excessive surface discharge .
Dirt ,moisture and corrosion are a cause of surface discharge .clean the battery
with a baking soda and water solution .do not allow the solution to get into the
battery.
[2]Static Battery Test (No Load)
This test checks for battery change state.
·Turn the headlights on for 15 seconds to dissipate battery surface charge.
IMPORTANT : The ignition switch
must be OFF when connecting or
disconnecting battery cables to
prevent damaging the vehicle
computer.
·Disconnect the negative (-)
battery terminal.
·Set the rotary switch to voltage.
·Connect the positive (+) lead to
the positive (+) battery post.
·Connect the negative (-) lead to
the negative (-) battery post.
A reading of less than 12.4V indicates an undercharged battery. Recharge
before testing. NO LOAD TEST
Meter Reading
Battery Charge
12.6V
100%
12.4V
75%
12.2V
50%
12.0V
25%
NOTE:
Leave the battery cable unhooked and proceed to the test
on the following page.
[3] Battery Test (Parasitic Load)
This is for excessive parasitic drain on the battery.
·Turn the ignition switch and all accessories OFF.
IMPORTANT: Do not start the vehicle during this test ; meter damage may
result.
·Set the rotary switch to 20A.
·Insert the positive (+) lead into the
10A meter terminal.
·Disconnect the battery positive (+)
cable .
·Connect the positive (+) lead to the
positive (+) battery terminal.
·Connect the negative (-) lead to
the Disconnect positive (+) battery
terminal.
Parasitic draw should not exceed
100mA.
If there excessive draw, remove the circuit fuse, one at a time, until the
excessive draw is located. Also check the non-fused applications such as head
lights, computer relays and capacitors in the instrument panel.
Reconnect the battery cable for the next test .

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[4] Battery Test (Load)
This tests the battery’s capacity to
deliver sufficient cranking voltage.
·Set the rotary switch to Voltage.
·Connect the positive (+) lead to
positive (+) battery terminal.
·Connect the negative (-) lead to
negative (-) battery terminal.
·Disable the ignition; crank the
engine for 15 seconds.
Check the Min. display. A reading of less than 9.60V@70℉indicates a weak
battery. Recharge/replace before testing.
Voltage Load Test
Meter reading
Battery/air temperature
10.0V
90F/33℃
9.8V
80F/27℃
9.6V
70F/21℃
9.4V
60F/16℃
9.2V
50F/10℃
9.0V
40F/4℃
8.8V
30F/-1℃
8.6V
20F/-7℃
NOTE:
·For each 10℉above or below 10℉, add or subtract 0.2 volt.
·Battery temperature can be checked with the meter
temperature probe.
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Rresistance, What is it ?
Resistance is an opposing force, created by a circuit or component, to the flow
of electrical current.
There is a small amount of natural resistance when voltage flows though wires,
switches, grounds or connections. The resistance increases beyond acceptable
limits if corrosion develops, fittings become loose or wire fray. Resistance
Increases each time something, such as wire, a switch, connections, or the
ground are added in the circuit.
Voltage Drop, What is it?
Voltage drop is the difference in voltage potential when measured across a

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circuit or component creating resistance.
The resistance decreases the amount of voltage available. The bulb will not
light or the motor will not turn if the voltage is too low.
Maximum Voltage Drop
Maximum voltage drop should not be more than 0.1 volt per
wire, ground, connection, switch or solenoid.
What should be tested?
Each wire, ground, connection, switch solenoid and the complete circuit should
be tested. Each connection point is a potential source of increased resistance.
Voltage Drop Testing
[1] Negative (-) Engine Ground
This test checks for engine ground efficiency.
·Set the rotary switch to Voltage.
·Touch the positive (+)
lead to the positive (+)
battery post and the
negative (-) lead to the
negative (-) battery
post. Note the
reading„this will be
the base voltage to
compare your test
voltage reading
against.
·Connect the positive
(+) lead to a clean
spot on the engine
block.
·Connect the negative (-) lead to the negative battery post.
·Disable the ignition so the engine doesn’t start; crank the engine for 2-3
seconds.
The example shown has 2 connectors, 1 wire, 1 ground and 1 terminal to
battery post. Avoltage drop of more than 0.5 volts would indicate a poor ground
circuit.
Clean and inspect the battery cable connections test and the ground; test
again.
Important: Repeat this test when the engine is thoroughly warmed up. Heat
expansion of metal may cause resistance to increase.
[2] Negative (-) Chassis Ground
This test checks for chassis ground efficiency.
·Set the rotary switch to Voltage.
·Establish the base voltage that you will compare test voltage against (see
base voltage, Volt Drop Test [1] ).
·Connect the positive (+) lead to the point on the fender, fire wall or vehicle
frame where the accessory ground is fastened .
·Connect the negative (-) lead to the negative battery terminal.
·Turn all of the accessories ON (bright lights, A/C fan –high ,rear window
defroster, windshield wipers ,etc.).
·Disable the ignition so the engine doesn’t start ; crank the engine for 2-3
seconds .
The example shown has 2 connectors, 1 wire , 1ground and 1 terminal to
battery post. Avoltage drop of more than 0.5 volts would indicate a poor ground
circuit .
Clean and inspect the battery cable connections and the ground ; test again .

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[3] Battery Power to Starter Solenoid (+)
This test checks battery source efficiency to the starter solenoid .
·Set the rotary switch to Voltage .
·Establish the base voltage that you will compare test voltage against (see
base voltage , Volt Drop Test [1] ).
·Connect the positive (+) lead to the positive (+) battery terminal.
·Connect the negative (-) lead to the positive (+) terminal on the starter
solenoid .
·Disable the ignition so the engine doesn’t start ; crank the engine for 2-3
seconds .
The example shown has 2 connectors and 1 wire , Avoltage drop of more than
0.3 volts would indicate a poor ground circuit .
Clean and inspect the battery cables and cable connections ; test again .
Important :Repeat this test when the engine is thoroughly warmed up .Heat
expansion of metal may cause resistance to increase .
[4] Battery Power to Complete Starter Circuit (+)
This test checks battery power efficiency to the starter through the starter
solenoid .
·Set the rotary switch to Voltage .
·Establish the base voltage that you will compare test voltage against (see
base voltage, Volt Drop Test [1] ).
·Connect the positive (+) lead to the positive (+) battery terminal .
·Connect the negative (-) lead the positive (+) terminal on the starter motor .
·Disable the ignition so the engine doesn’t start ; crank the engine for 2-3
seconds.
The example shown has 4 connectors and 2 wire , and 2 solenoid
connections .Avoltage drop of more than 0.8 volts would indicate a poor ground
circuit .
Clean and inspect the battery and starter cables , solenoid and cable
connections ; test again.
Note : A defective starter solenoid may cause an excessive voltage drop ;
check the cables and connections before replacing the solenoid .
Starter Motor Testing
[1] Starter –Current
The battery tests and the voltage drop tests have verified that there is adequate
battery voltage at the starter . Next , check for excessive starter motor current
draw.
·Connect a current clamp around the negative (-) or positive (+) battery cable .
·Set the rotary switch to the 400mV setting.
NOTE: 1mV=1Amp.
·The Min reading will be the negative current draw .
·Disable the ignition so the engine doesn’t start ; crank the engine for 2-3
seconds .
NOTE:
The current clamp measures amps in the direction of electrical flow. Make sure
the arrow on the clamp is pointed in the directionof the current flow inthe cable.
Quick Test
Turn the ignition and all accessories OFF, Place the clamp on the battery
cable ,then turn the headlights on . If the reading is not negative, disconnect the
clamp, turn it over and reconnect .
Approximate Aperage Draw
4Cyl
150-180 Amp, Maximum

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6-8Cyl, Under 300 CID
180-210 Amp, Maximum
6-8Cyl, Over 300 CID
250 Amp, Maximum
Charging System Tests
[1] Battery (+)
This test checks for alternator output voltage at the battery.
·Set the rotary switch to Voltage .
·Connect the positive (+) lead to the positive (+) battery terminal.
·Connect the negative (-) lead to the negative (-) battery terminal.
·Mark sure all vehicle accessories are turned OFF.
·Start the engine and hold at 1500RPM.
A reading of 13.1-15.5 volts is an acceptable charging rate, If the voltage is low
check for:
·Loose, cracked, or glazed drive belt .
·Loose or faulty wires or connectors.
·Defective alternator or regulator. See [2] Alternator Voltage Output (+),
Loaded.
[2] Alternator Voltage Output (+), loaded
This test checks for alternator output voltage. This test is necessary only if the
vehicle failed [1] Battery (+) test.
·Set the rotary switch to the Voltage setting.
·Connect the positive (+) lead to the battery (B+) output post on the back of the
alternator.
·Connect the negative (-) lead to the negative (-)battery terminal.
·Start the engine and hold a 1500RPM.
A reading of 13.1-15.5 volts is an acceptable Charging rate.
[3] Alternator Amperage (A) Output, Battery
This test checks for alternator charging rate efficiency at the battery.
·Connect cureent Clamp (RPM-100, option) leads to the meter .
·Connect the Current Clamp around the negative (-) or positive (+) battery
cable .
·Set the rotary switch to the Voltage setting .
NOTE: 1mV=1Amp
·Mark sure all vehicle accessories are turned OFF.
·Start the engine and hold at 1500 RPM.
TheAmperage reading should be 5 amps or better.
NOTE:
The current clamp measures amps in the direction of electrical flow. Make sure
the arrow on the clamp is pointed in the directionof the current flow inthe cable.
Quick Test :
Place the clamp on the battery cable , then turn the headlights on. If the reading is not
negative, disconnect the clamp, turn it over and reconnect.
Ignition System Tests
[1] Ignition Coil, Primary Resistance Test (Ω).
This test checks primary winding resistance.
IMPORTANT: Test the ignition coil cold and hot.
·Set the rotary switch to the Resistance (Ω) setting.

- １４ -
INSERT:
·Black lead in COM terminal.
·Red lead in V/ ΩRPM
terminal.
·Disconnect the coil from the
vehicle wiring harness.
·NOTE:
The resistance in the meter
leads must be subtracted to get
an accurate measurement at
the 0.50-2.0 range. Short the
leads together and press the “TEL”Button . The meter will automatically
subtract the resistance in the leads.
·Connect the negative (-) lead to the negative (-) terminal on the coil.
·Connect the positive (+) lead to the positive (B+) terminal on the coil.
Typical measurements are between0.50-2.0 Ω’s consult the manufacturer’s
specifications for required resistance measurements.
[2] Ignition Coil , Secondary Resistance Test (Ω)
This test checks secondary winding resistance .
IMPURTANT: Test the ignition coil
cold and hot
·Set the rotary switch to the
Resistance (Ω) setting .
INSERT:
·Black lead in COM terminal .
·Red lead in V/ΩRPM terminal .
·Disconnect the coil from the
vehicle wiring harness .
·Connect the negative (-) lead to
the high tension terminal on the
coil .
·Connect the positive (+) lead to
the positive (B+) terminal on the coil.
Typical measurements are between 6000-30000’s Consult the manufacturer’s
specifications for required resistance measurements.
[3] Secondary Ignition Wire Resistance Test (Ω)
This test checks for open circuits or high resistance in the secondary (sparkplug)
wires.
IMPORTANT: Twist and bend the sparkplug wire while measuring the
resistance for this test .
·Set the rotary switch to the Resistance (Ω) setting.
INSERT:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the test probes to opposite ends of the sparkplug wire.
Typical measurements are approximately 1.000Ω’s per inch of wire . For
example, 10 inch cable=10.000Ω.
[4] Distributor Cap/Rotor Resistance Test (Ω)
This test checks for open circuits or high.
Resistance in the distributor cap and rotor.
·Set the rotary switch to the Resistance (Ω).
INSERT:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
Dist. Cap Center Connector Test:
Connect the test probes to opposite ends of the distributor cap terminal .
In general, resistance (Ω) should be 5k-10k. Refer to the manufacturer’s

- １５ -
specifications.
Rotor Test:
Connect the test probes to opposite ends of the rotor contacts .
In general, resistance should be 0.1(Ω) or less. Refer to the Manufacture’s
specifications.
[5] Pick-up Coil Resistance (Ω)/Voltage Test (V)
·The Resistance test checks for open circuits or high resistance.
·The Voltage test compares voltage output to resistance.
Test Procedure
·Set the rotary switch to the Resistance(Ω).
INSERT:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the test probes to the pick-up coil lead .
Resistance Specifications
The majority of the pick-up coils will test between 500-1500Ω’s resistance. See
manufacture’s specification for required range.
·Set rotary switch to volts. Press the select button , Alternate Function button
to select AC.
·Crank engine 10-15 seconds at normal speed; measure voltage.
Resistance Test/Voltage Output
Resistance(Ω) on a “good ”pickup coil will matchAC output voltage (Ex.,950
Ω’s=950mV output). Resistance can be good but voltage low if the magnet has
lost magnetism or if the reluctor is too far from the stator (Airgap).
[6] Hall Effect Sensor Voltage Test (V)
This test checks for switching action in any hall Effect sensor (Ignition, RPM,
Crankshaft, etc.)
·Set the rotary switch to the Voltage (V) position.
INSERT:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the Black test probe to the negative (-) post on the battery.
·Turn the ignition key ON. Touch the Red (+) test probe to the three test point
shown.
·Ground reading should be the same voltage as the ground (Computer or
battery ).
·Supply line reading should be the same voltage as the input source (Computer
or battery).
·Signal line reading should be 0 or the same voltage as the input source
(Computer or battery). The reading will toggle high and low as the shutter
rotates.
Basic Diagnostic Testing
This chapter describes a computer controlled sensor and actuator system
typically Found on today’s automobile.
Test procedures are also provided for the basic ground of electrical input and
output components commonly found in a computer controlled automotive
system. The test procedures are, due to the complexity of components, general
theory tests. Be sure to consult the vehicle service manual for component
schematics and test specifications.
Computer Controlled Systems
A need for better fuel economy and lower emissions resulted in today’s
automobiles Utilizing computer controlled functions that were previously
activated bymechanical, Electrical and vacuum devices.

- １６ -
Computerized vehicle control systems are made up of three basic component
groups. These groups are:
1. Sensors: they are input devices that supply information about engine
operating conditions and the surrounding environment to the vehicle
computer.
2. Engine Control Module: a vehicle computer that processes the information
supplied by the sensors, then sends an electronic command to the appropriate
components actuators.
3. Actuators: these are output devices that may be electrical, mechanical or
vacuum components controlled by the vehicle computer.
Typical Sensors
Typical Actuators
Basic Diagnostics for the computer
Controlled Engine
There are two important steps that must always be followed when diagnosing
and repairing vehicles with computer controls.
·Do basic engine diagnostics first .Many problems can be traced to lack of
routine maintenance on components such as plug wires, filters and spark plugs .
Also check for vacuum leaks on any vehicle, new or old, A completes engine
diagnosis should precede any electrical system diagnostics.
·Follow the published diagnostic Charts Exactly through every step to mark a
repair on computer component.
Self-Diagnostic Computer Systems
One of the functions of the vehicle computer is to record fault codes produced
when a sensor or actuator fails. These failures are usually displayed as a
“Current Code”or as an “Intermittent Failures”. Be aware, however, that some
vehicle manufacturers use different terminology and older vehicles do not have
all of ground of codes described.
Current Codes are faults that are active.
·Hard Failure causes the dash “check engine”light to remain ON.
·Intermittent Failure causes the dash “check engine”light to flicker and then go
OFF after a short period of time. Generally the trouble code stays in the
computer memory.
History Codes are stored codes for faults that have occurred in the past.
Failure Codes
When a failure is detected be the computer, it stores the information in the form
of “Fault Codes”(also known as Trouble Codes or Service Codes). These Fault
Codes are usually a two or three digit number that identifies the electrical circuit
effected. Once these codes have been read the vehicle repair can be stares.
Be sure to closely follow the vehicle service manual diagnostic procedures,
repairs and specifications.
Component Testing
Component testing with a meter generally requires detailed schematics and
specifications that are provided by the manufacture. The following section
provides general information for the main groups of sensors (input) devices and
actuators (output) devices.
The primary input devices (sensors) are:
·Temperature sensors
·2-wire devices
·3-wire devices
·Oxygen sensor
·pressure sensors
Primary output devices (actuators) are a form of an electromagnet that is either
ON or OFF. The ON/OFF signal, in general , will be in one of three
configurations:
·ON of OFF only (switch)
·Pulse width in a specified length of time (fuel injector)
Coolant
Sensor
Vacuum
Sensor
Throttle
Position
Sensor
RPM
Barometric
Sensor
Oxygen
Sensor
Eleatro
Mechonic
al
carburelor
Fuel
injoctio
n
Ignltion
Spark
advance
Exhaust Gas
Recirculeting
Valva
Air
Pump
Canister
Purge
Torque
Converter
clutch
Vehicle
Computer

- １７ -
·Duty cycle measured in percent of high or low time or dwell degrees
(mixture control solenoid)
Duty Cycle, What is it ?
Duty cycle is the percentage (%)
of time a voltage is positive
compared to negative:ON
compared to OFF. For example;
duty cycle measurements are
used for Mixture control solenoids.
The amount of ON time is
measured as a percent of the total
ON/OFF cycle. The meter can
read the negative (-) or positive (+)
slope and display it as a percent (%) of the total cycle.
Frequency (Hz), What is it?
Frequency is the number of times a voltage pattern repeats positive compared
to negative: ON compared to OFF,
during one (1) second of time. For
example: frequency(Hz)
measurements are specified for
digitally controlled manifold
Absolute Pressure sensors. The
frequency of the ON/OFF signals
per second are measured and
displayed.
Frequency(Hz) is shown as
Analog: A continuous positive to
negative cycle; or Digital: A
positive to negative/ON to OFF
cycle.
Pulse Width. What is it?
Pulse width is the length of time
an actuator is energized. For example; fuel injectors are activated by an
electronic pulse from the engine control module. This pulse generates a
magnetic field that pulls the injector nozzle valve open. The pulse ends and the
injector nozzle is closed. This “open to close”time is the pulse width and is
measured in milliseconds (mS).
Typical Port fuel injectors(TBI) operate with a single ON to OFF electrical
pulse.
Typical Port Throttle Body injectors (TBI) operate with an ON to HOLD to OFF
electrical pulse. This method creates a double electrical “spike”. An
oscilloscope is required to measure this type of pulse.
Component Tests (input)
[1] Temperature Tests
Many components that regulate temperature can be tested be measuring the
surface temperature of the area surrounding the component.
·Connect the temperature probe to the meter.
·Set the rotary switch to the Temperature position.
·Touch the end of the temperature probe directly to the surface of the
component to be tested.
Compare your readings with the manufactures Specifications. The temperature
should be within ±10℉(±5℃) of the data stream Values.
Some of the components that can be tested for Temperature variation are:
·Radiators
·Transmission
·Heaters
·A/C Condensers
·A/C Evaporators
·Engine Coolant Sensors
·Air Temperature Sensors
[2] Thermistor (Variable Resistance, 2-wire) Tests
Thermistor are variable resistors that are sensitive to temperature level
changes. As the temperature changes, the thermistor’s resistance value
changes.
·Select the Ohms (Ω) range the rotary switch .
·Connect the test probes to the sensor terminals.
The Ohms reading should match the temperature of the sensor (see
manufacturer’s specifications).

- １８ -
Typical thermistor applications are:
·Engine Coolant Temp. (ECT)
·Air Charge Temp. (ACT)
·Manifold Air Temp. (MAT)
·Vane Air Temp. (VAT)
·Throttle Body Temp. (TBT)
Voltage Presence
·Disconnect the vehicle wiring harness at the sensor.
·Select the Voltage range with the rotary switch.
Insert:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the test probes in parallel:
positive (+) to the circuit coming from the power source, negative (-) to the
negative circuit from the sensor.
·Turn the ignition switch ON; do not start 10 the engine.
Measurement should be 5-9 volts (check the manufacture’s specifications).
Voltage Change Connect jumper wires between the connector and the sensor.
·Connect the test probes in parallel:
Positive (+) to the circuit coming from the power source, negative (-) to the
Negative circuit from the sensor.
·Start the engine.
The voltage should change as the temperature changes. This is the signal that
is sent to the computer for processing. Refer to the manufacturer’s
specifications. If the voltage change is not within specifications, look for
sources of resistance due to poor connectors, connections or breaks in the
wiring.
[3] Potentionneter (Variable Resistance, 3-wire) Tests
The potentiometer is a variable resistor. The signal it generates is used by the
vehicle computer to determine position and direction of movement of a device
within the component.
Resistance
·Set the rotary switch to the Resistance (Ω) setting.
·Disconnect the sensor.
·Connect the test probes to the signal line and to the ground (refer to
manufacturer’s schematic).
Watch the display; the Ohms reading should change as the signal arm on the
potentiometer is moved (signal sweep).
Typical potentiometer applications are:
·Throttle position Sensor (TPS)
·Exhaust Gas Recirculation valve position Sensor (EVP)
·Vane Flow Meter(VAF)
Potentiometers (Variable Resistance, 3-wire) Tests
Reference Voltage Test
·Disconnect the vehicle wiring harness at the sensor.
·Select the Voltage range with the rotary switch.
Insert:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the test probes in parallel:
Positive (+) to the computer reference voltage circuit, negative (-) to the
negative system ground circuit from the sensor.
·Turn the ignition switch ON : do not start the engine.
Watch the display. Reading should be 5-9 volts (check the manuacturer’s
specifications).
Potentiometers (Variable Resistance, 3-wire) Tests
Voltage Change
·Connect jumper wires between the connector and the sensor.
·Connect the test probe in parallel:
positive (+) to the signal line, negative (-) to the ground circuit.
·Turn the ignition key ON, do not start the engine.
·Observe the display. The voltage drop should change as the position of the
signal arm on the potentiometer moves (signal sweep).
Refer to the manufacturer’s specifications. If the voltage change is not within
specifications, look for sources
of resistance due to poor
connectors, connections or
breaks in the wiring.
[4] Oxygen Sensor (02) Test
The Oxygen sensor samples
the amount of Oxygen in the
exhaust stream. The voltage
produced by the 02 sensor is a
direct ratio to the oxygen level

- １９ -
in the exhaust stream this voltage is used by the computer to change the
air/fuel mixture.
This test will check oxygen sensor signal output levels.
·Disconnect the vehicle wiring harness at the sensor. Install a jumper wire.
·Select the voltage range with the rotary switch.
Insert:
·Black lead in COM terminal.
·Red lead in V/Ω/RPM terminal.
·Connect the test probes in parallel:
positive (+) to the jumper wire, negative (-)to the engine ground.
·Vehicle engine must be running at operating temperature (fast idle at
2000RPM for two minutes).
Voltage readings should move between 0.2(lean) and 0.8 (rich). The average
DC voltage should be around 0.50.
[5] Pressure sensor Test
The electrical tests for pressure sensor such as the ManifoldAbsolute Pressure
(MAP) and Barometric Pressure (BARO) vary greatly, depending upon type and
manufacturer, consult the vehicle service manual for the schematic,
specifications and test procedures.
General Testing Procedures
Note : You cannot do a resistance (Ω) test for pressure sensors.
Analog Sensor
An analog sensor can be tested with the same series of voltage (V) tests
suggested for 3-wire potentiometet voltage tests. In place of “sweeping”the
sensor, a vacuum pump is generally used to vary the pressure onthe sensor. In
all cases, refer to a vehicle service manual for the correct procedure.
Component Test (Output)
Output Devices
The electrical tests for output devices vary greatly, depending upon type and
manufacturer. Consult the vehicle service manual for the schematic,
specifications and test procedures.
Primary output devices (actuators) are from of an electromagnet that is either
ON/OFF. The ON/OFF signal, in general, will be in one of three configuration:
·ON/OFF only (switch) check for continuity with the switch in the ON and OFF
position.
·Pulse width (fuel injector) measure the ON time (pulse).
·Duty cycle (Mixture Control Solenoid) measure the percent of high (+) or
low (-) time in a duty cycle. In most cases the low (-) time is the on time.
Maintenance Fuse and Battery Replacement
WARNING:
·Avoid electrical shock; remove test leads before opening case.
·Do not operate the meter or rotate the meter switch when the case is open.
1. To replace a battery or fuse, loose the four screws in the case back and
remove the case by lifting up and forward.
·Replace the battery with an 9 volt alkaline battery.
2. To replace fuse, firmly grasp the printed circuit board (PC boards by the
edges and lift up and out of the case.
IMPORTANT:
·To prevent contamination of the circuits, your hands must be clean and the
printed circuit board must be help by the edges.
·Replace the fuse with the same type of fuse.
◎10A is a F10A ,250V high energy, fast acting fuse.
◎mA is a F500mA, 250v high energy, fast acting fuse.
·Mark sure the replacement fuse is centered in the fuse holder.
3.Carefully re-insert the PC boards into the case. Re-assemble the case, then
fasten the four screws.
Trouble Shooting
1.Meter will not turn ON.
·Check the battery contacts for a tight fit.
·Check for a minimum battery voltage of 8.0 volts.
·Mark sure the battery wire, are not pinched in the cafe.
2. Ampere reading is erratic or there is no reading at all.
·Disassemble the meter back cover and test the fuses for continuity.
3. Meter reading is erratic.
·Printed circuit board contaminated from handling with hands.
·Low battery.
·Open circuit in a test lead (frayed or broken wire).
·Wrong range selected.
·For frequencies below 1Hz, the display will show 00.00Hz.
·“Blown”fuse.