Precor C966i User manual

C956i, C966i (Gen 06) Treadmill
Page 1
C956i, C966i Treadmill
Warning: This service manual is for use by Precor trained service providers only.
If you are not a Precor Trained Servicer, you must not attempt to service any Precor Product;
Call your dealer for service.
This document contains information required to perform the majority of troubleshooting, and
replacement procedures required to repair and maintain this product.
This document contains general product information, software diagnostic procedures (when
available), preventative maintenance procedures, inspection and adjustment procedures,
troubleshooting procedures, replacement procedures and electrical block and wiring diagrams.
To move directly to a procedure, click the appropriate procedure in the bookmark section to the
left of this page. You may “drag” the separator bar between this page and the bookmark section
to change the size of the page being viewed.
© 2006 Precor Incorporated
Unauthorized Reproduction and Distribution Prohibited By Law
20077-111

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Section One - Things you Should Know
About This Appendix
The C956i, C966i (Gen 06) incorporate new drive motor system and display systems. The drive
motor is a three phase AC motor. The drive motor controller converts a single phase AC input
into three phase motor control.
Section One, Things You Should Know. This section includes technical specifications. Read
this section, as well as the C956i, C966i Treadmill Owners Manual, before you perform the
maintenance procedures in this manual.
Section Two, Software Features. Precor’s C956i, C966i Treadmills are programmed with
several diagnostic and setup features. This section contains the procedures you need to access
the diagnostic features on this treadmill.
Section Three, Checking Treadmill Operation. This section provides you with a quick way of
checking treadmill operation. Check treadmill operation at the end of a maintenance procedure
and when it is necessary to ensure that the treadmill is operating properly.
Section Four, Inspection and Adjustment Procedures. Perform inspection procedures when
a trouble symptom points to a particular problem and after removing and replacing major
components. Many maintenance problems can be fixed by adjusting various treadmill
components. This section also provides you with the step-by-step procedures required to make
these adjustments.
Section Five, Troubleshooting Procedures. The diagnostic and troubleshooting procedures
contained in this section should be performed when it is necessary to isolate a problem to a
particular component.
Section Six, Replacement Procedures. When a treadmill component must be replaced, go to
this section and follow the step-by-step procedures required to remove and replace the
component.
Section Seven, Technical Diagrams and Parts Lists. This section includes wiring diagrams,
and block diagrams for the C956i, C966i Treadmills.

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Safety guidelines you should know and follow include:
• Read the owner’s manual and follow all operating instructions.
• Operate the treadmill on a solid, level surface.Visually check the treadmill before beginning
service or maintenance operations. If it is not completely assembled or is damaged in any
way, exercise extreme caution while operating and checking the treadmill.
• When operating the treadmill, do not wear loose clothing. Do not wear shoes with heels or
leather soles. Check the soles of your shoes and remove any embedded stones. Tie long
hair back.
• Do not rock the unit. Do not stand or climb on the handlebars, display enclosure, or cover.
• Do not set anything on the handlebars, display enclosure, or cover. Never place liquids on
any part of the treadmill, while performing service.
• To prevent electrical shock, keep all electrical components away from water and other
liquids.
• Do not use accessory attachments that are not recommended by the manufacturer-such
attachments might cause injuries.
•
• Removing the hood exposes high voltage components and potentially dangerous
machinery. Exercise extreme caution when you perform maintenance procedures with the
hood removed.

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General Information
For the latest exploded view diagram, part number and part pricing information, visit the Precor
dealer website at “www.precor.com/connection.

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Procedure 2.1 - Accessing the Diagnostic Software
The treadmill's diagnostic software consists of the following modes:
• Display Test
• Keyboard Test
• Heart Rate Test
• Machine Test
Belt Speed
Incline
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. Using the RESET key and the numeric keypad, press keys RESET,5,1,7,6,5,7,6,1,
sequentially.
3. Hardware Validation will scroll across the display followed by DISPLAY TEST.
Diagram 2.1 - C956i, C966i Treadmill Display
Numeric Keypad
Reset Key
OK Key
Back Key

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4. Press the OK key, the upper most group of LED’s will illuminate on the display. Check the
display to ensure that all LED segments are illuminated.
5. Press the OK key four more times to display the remaining LED groups. Check each display
group to ensure that all LED segments are illuminated.
6. Press the BACK key then the key, KEYBOARD TEST will scroll across the display.
7. Press the OK key, a representation of all of the keys on the console will be displayed.
Pressing a key on the console will cause the representation of that key to go off. Press all of
the keys on the console to ensure that all of the keys are functioning.
8. Press and hold the BACK key then the key, HEART RATE will be displayed.
9. Grasp both of the heart rate grips on the handlebar, after a couple of seconds the heart rate
will be displayed in the heart rate and smart rate displays.
10. Use chest strap transmitter or a test transmitter to test the wireless heart rate function, after
a couple of seconds the heart rate will be displayed in the heart rate and smart rate displays.
11. Press the BACK key then the key, MACHINE TEST will scroll across the display.
12. You may now proceed to either the belt speed test or the incline test. Press the key once
to access the belt speed test or twice to access the incline test.
13. BELT SPEED test. Press the OK key, the console will display the power bits (PWRB), Press
the SPEED key to start the treadmill running belt, the display will indicate the power bits,
the elapsed time and the actual speed (in either miles per hour or kilometers per hour
depending on the club parameters setting, see Procedure 2.3).
14. Press the key, the console will display the motor current (AMPS), the elapsed time and
the actual speed.
15. Press the BACK key to exit the belt speed test.
16. INCLINE test. The console will display the analog to digital (A/D) incline position number
and the incline position in percent of incline. Press the inline ,keys to operate the incline
through out its range.
17. Press the BACK key to exit the incline test.
18. Press the RESET key to exit the hardware validation test.

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Procedure 2.2 - Displaying Information
The information display will access the following data;
• Odometer
• Hour Meter
• U-Boot Software
• U-Base Software
• Lower Software
• Serial Number
• Usage log
• Error Log
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. With the PRECOR banner scrolling, press the keys RESET,6,5, sequentially.
3. DIAGS-INFORMATION DISPLAY will scroll across the display.
4. Use the ,keys to move to the desired display shown in the list above.
5. ODOMETER display. Press the OK key.
6. The odometer will be displayed as 1234567 MILES or 1234567 KM depending on club
parameter settings (See Procedure 2.3). The odometer is also used to provide the “distance
stamp” for the error code log
Note: The odometer data is stored in non-volatile memory on the upper PCA. If the upper PCA
is replaced the odometer data will be lost.
7. Press the BACK key to exit the odometer display.
8. HOUR METER display. Press the OK key.
9. The operating time of the unit will be displayed as 12345 HOURS. The operating time is
defined as total amount of time that the unit has operated in program modes with the drive
motor running. The hour meter is also used to provide the “time stamp” for the error code
log.
10. Press the BACK key to exit the hour meter display.
11. U-BOOT SW display. This display the installed version of upper boot software. The boot
software is used to upload new software into the upper display PCA.
12. Press the OK key. The software part number will be displayed as XXXXX-XXX.

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13. Press the BACK key to exit the U-Boot SW display.
14. U-BASE SW display. This display the installed version of upper PCA software.
15. Press the OK key. The software part number will be displayed as XXXXX-XXX.
16. Press the BACK key to exit the U-Base SW display.
17. LOWER SW display. This display the installed version of lower PCA software.
18. Press the OK key. The software part number will be displayed as XXXXX-XXX.
19. Press the BACK key to exit the lower SW display.
20. SER. NUMBER display. Press the OK key.
21. The treadmill’s serial number will be displayed. The serial number may be incorrect or not
displayed if the upper PCA has been replaced.
22. Press the BACK key to exit the serial number display.
23. USAGE LOG display. Press the OK key.
24. Use the ,keys to move through the list of programs. A message will scroll describing the
program, the number of times and the number of minutes the program was used.
25. Press the BACK key to exit the usage log display.
26. ERROR LOG display. Press the OK key, the quantity of errors in the log will be displayed.
27. Press the OK key, the most recent error will be displayed first.
28. Use the ,keys to move through the list of errors. The error messages will list the error
name, the odometer reading when the error occurred, the hour meter when the error
occurred and the drive motor current reading when the error occurred.
29. If you wish to clear the error log, press and hold the QUICK START key. The message
HOLD TO CLEAR ERRORS will be displayed. The error log will be cleared when the
message NO ERRORS is displayed.
30. Press the RESET key to exit the information display.
31. Please note that the ERROR LOG may also be accessed at any time by pressing and
holding the RESET key for four seconds. If the error log does not contain any errors, the
message STUCK KEY will be displayed.

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Procedure 2.3 - Setting Club Parameters
This procedure allows you to change the following club settings:
• Safety Code
• Select Language
• Select Units
• Set Max Workout Time
• Set Max Pause Time
• Set Cool Down Time
• Set Speed Limit
• Set Incline Limit
• Hidden Programs
• Remote Speed Control
• Set Custom Program 1
• Set Custom Program 2
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. With the banner scrolling, press keys RESET,5,6,5,1,5,6,5, sequentially.
3. Use the ,keys to move to the desired display shown in the list above.
4. DIAGS-SET CLUB PARAMETERS will scroll across the display.
5. SAFETY CODE display. The safety code, when enabled, makes the user enter a password
in order to start the treadmill. Press the OK key.
6. Use the ,keys to toggle between ENABLED and DISABLED.
7. Press the BACK key to exit the safety code display.
8. SELECT LANGUAGE display. Press the OK key.
9. Use the ,keys to toggle between the available languages.
10. Press the BACK key to exit the select language display.
11. SELECT UNITS display. Press the OK key.
12. Use the ,keys to toggle between U.S (miles per hour) and METRIC (kilometers per
hour).
13. Press the BACK key to exit the set units display.

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14. SET MAX WORKOUT TIME display. Press the OK key.
15. Use the ,keys to select the maximum time a user can remain in a program.
16. Press the BACK key to exit the set max. workout time display.
17. SET MAX PAUSE TIME display. Press the OK key.
18. Use the ,keys to select the maximum time a program will remain in the pause mode.
19. Press the BACK key to exit the set max. pause time display.
20. SET COOL DOWN TIME display. Press the OK key.
21. Use the ,keys to select the cool down time.
22. Press the BACK key to exit the set cool down time display.
23. SET SPEED LIMIT display. Press the OK key.
24. Use the ,keys to select the maximum allowable treadmill speed.
25. Press the BACK key to exit the set speed limit time display.
26. SET INCLINE LIMIT display. Press the OK key.
27. Use the ,keys to select the maximum allowable incline setting.
28. Press the BACK key to exit the set incline limit time display.
29. HIDDEN PROGRAMS display. Press the OK key.
30. Use the ,keys to toggle between HIDE PROGRAMS and SHOW PROGRAMS.
31. Press the BACK key to exit the hidden programs display.
32. REMOTE SPEED CONTROL display. Remote speed control allows the treadmill speed to
be controlled by an external source such as InSite. Press the OK key.
33. Use the ,keys to toggle between ENABLED and DISABLED.
34. Press the BACK key to exit the remote speed control display.
35. SET CUSTOM PROGRAM 1 display. Allows programing of the custom program 1. Follow
the instructions scrolling on the display to program the custom course. Use the ENTER key
to save changes and exit or the BACK to exit without saving changes.

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36. SET CUSTOM PROGRAM 2 display. Allows programing of the custom program 2. Follow
the instructions scrolling on the display to program the custom course. Use the ENTER key
to save changes and exit or the BACK to exit without saving changes.

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Procedure 2.4 - Documenting Software Problems
When a problem is found with the software in the upper or lower PCA, record the information
listed below.
When a problem occurs, record the following information:
• Model and serial number
• Software version number
• Program number running when the problem occurred
• A description of:
•a. What happened or failed to happen.
b. The action taken by the user just before the problem occurred.
c. Problem-related information (such as how far into the program the problem occurred,
the work level being used when the problem occurred, error code displayed, etc.).
• The frequency of occurrence.

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Section Three - Checking Treadmill Operation
This section provides you with a quick method of checking treadmill operation. Check treadmill
operation at the end of a maintenance procedure and when it is necessary to ensure that the
treadmill is operating properly.
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. Operate the treadmill in the Manual program. Adjust the speed of the running belt to 2–3
m.p.h. Operate the treadmill for at least 5 minutes.
a. Concentrate on the feel of the running belt and the sound of the drive motor and rollers.
Be on the alert for unusual noises, smells, or vibrations.
b. Observe the LED’s on the electronic console. Make sure that each LED lights as the in-
formation corresponding to that LED is displayed on the electronic console.
c. Enter the diagnostics program (see Procedure 2.1) and log the power bits under loaded
and unloaded conditions.
3. Press the STOP key. When the treadmill comes to a stop, view the electronic console as the
treadmill scans time, speed, distance and percent of incline.
4. Press the INCLINE ▲key while viewing the electronic console. Confirm that the running
bed inclines and the incline display increments to 15% as the INCLINE ▲key is pressed.
5. Press the INCLINE ▼key while viewing the electronic console. Confirm that the running bed
returns to a level position and the incline display decrements to 0% as the INCLINE ▼key is
pressed.
6. Turn off the treadmill with the circuit breaker, then unplug the treadmill from the wall outlet.

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Procedure 4.1 - Calibrating the Incline Motor
1. Set the treadmill circuit breaker in the “off” position and unplug the line cord from the wall
outlet.
2. Remove the hood.
3. Place the treadmill on its right side. Remove hitch and clevis pins that secure the incline
tube to the incline platform. See Diagram 4.1.
Diagram 4.1 - incline Motor Mounting
4. Plug the power cord into the wall outlet, set the treadmill circuit breaker in the “on” position.
If the lift was not set at 0% incline the lift motor will immediately start to operate. The lift
motor will continue to operate until the system is at 0% incline.
5. With the system at 0% incline, rotate the incline tube until the distance from the top of the
incline tube to the incline motor is 1-1/4 inch. See Diagram 4.1. While rotating the incline
tube, be sure the incline motor drive screw does not rotate. If the drive screw is rotated,
return to step 4 and repeat steps 4 and 5.
6. Set the treadmill circuit breaker in the “off” position and remove the line cord from the wall
outlet.
7. Replace the clevis and hitch pins removed in step 3. Return the treadmill to an upright
position.
8. Plug the line cord into the wall outlet, set the treadmill circuit breaker in the “on” position.
1-1/4”

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9. Check the calibration of the incline system by performing the following steps:
a Press the INCLINE  key until maximum incline is obtained, 15%.
b Press the INCLINE  key to minimum incline is obtained, 0% on C956i treadmills or
-3% on C966i treadmills.
12. Re-install the hood.

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Procedure 4.2 - Adjusting Drive Belt Tension
1. Set the treadmill circuit breaker in the “off” position and unplug the line cord from the wall
outlet.
2. Remove the hood.
3. Place the drive belt tension gauge on the drive belt as shown in Diagram 4.2.
Diagram 4.2 - Drive Belt Tension Gauge
4. The gauge should read approximately 80 inch/pounds. The drive belt tension is acceptable
if it is in the range of 70 to 90 inch-pounds.
5. If the drive belt tension is less than 70 or greater than 90 inch/pounds, slightly loosen the
four drive motor mounting bolts. The drive motor mounts on slotted holes allowing the drive
motor to be move forward or rearward. Move the drive motor forward or rearwards, as
required, until the belt gauge reads approximately 80 inch/pounds and tighten the four drive
motor mounting bolts. See Diagram 4.3. Momentarily remove the drive belt tension gauge
from the drive belt. Replace the drive belt tension gauge on the drive belt and re-adjust the
drive belt tension, if necessary. Torque the four drive motor mounting bolts to 204 inch
pounds (17 foot pounds).

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Diagram 4.3 - Drive Belt Adjustment
6. Re-install the hood.
7. Plug the line cord into the wall outlet and set the treadmill circuit breaker in the “on” position.
8. Check treadmill operation per Section 3.

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Procedure 5.1 - Troubleshooting the Keypad and Upper PCA
Procedure
Note The red wire on the cables shown in Diagram 5.1 denotes pin 1. When these cables are
inserted into their connectors, the red wire must align with the pin 1 designation on the PCA.
1. Set the treadmill’s on/off switch in the “off” position. Remove the display back plate and
display face per Procedure 6.10.
2. If the message STUCK KEY is displayed when the treadmill is turned on, skip to step 23.
3. If a key does not function, skip to step 18.
4. If the display does not illuminate, continue with step 5.
Diagram 5.1 - Display Face, Rear View
5. If the upper PCA is not illuminating, skip to step 12.
6. If the metrics PCA is not illuminating, continue with step 7.
7. Un-clip the metrics PCA from the display face and rotate it so that the front of the PCA is
visible. Set the treadmill’s on/off switch in the “on” position.
Upper PCA
Metrics PCA
D-Pad Assembly
Keypad Cable
Stop Switch
Connector
ISP Connector
J4
Entertainment
Connector J1
D-Pad Cable Metrics Cable

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8. With a DC voltmeter, measure between TP1 (+8V) and TP3 (DGND) for 8 Vdc and between
TP4 (+5V) and TP3 (DGND) for 5Vdc. See Diagram 5.2.
Diagram 5.2 - Metrics PCA, Front View
9. If 5 Vdc is not present on TP4 and 8 Vdc is present on TP1, replace the metrics PCA.
10. If 8 Vdc is not present on TP1 and the upper PCA is illuminating normally, replace the cable
between the upper PCA and the metrics PCA.
11. If you have performed steps 7 - 10 and the metrics PCA still does not illuminate, contact
Precor customer support for assistance.
12. Set the treadmill’s on/off switch in the “on” position.
13. With a DC voltmeter, measure between pins 2 and 6 of J1 (ISP) for 5 Vdc and between pins
4 and 5 of J4 (entertainment) for 8 Vdc.
14. If 5 Vdc is not present on J1 and 8 Vdc is present on J4, replace the upper PCA.
15. If 8 Vdc is not present on J4, temporarily replace the upper PCA to power control module
with a known good cable.
16. If the upper PCA illuminates normally, replace the upper PCA to power control module cable
permanently. If the upper PCA still does not illuminate, replace the power control module.
17. If you have performed steps 12 - 16 and the upper PCA still does not illuminate, contact
Precor customer support for assistance.
18. Set the treadmill’s on/off switch in the “on” position.
19. If none of the keys on the display are functioning, check the stop switch cable connection to
the upper PCA. If the stop switch is not connected or the stop switch is not functioning, none
of the display keys will operate. This feature insures that the treadmill has a functioning stop
switch when it is in use.
20. If a particular key is not functioning, perform the keyboard test in Procedure 2.1. If the test
verifies that the key is not functioning, replace the display face.
TP1 (+8V)
TP3 (DGND) TP4 (+5V)

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21. If the display face has been replaced and the same key is still not functioning, replace the
upper PCA.
22. If you have performed steps 18 - 22 and the same key is still not functioning, contact Precor
customer support for assistance.
23. Remove the keypad cable from the upper PCA. See Diagram 5.1.
24. Set the treadmill’s on/off switch in the “on” position.
25. If the STUCK KEY message is no longer displayed, replace the display face.
26. If the STUCK KEY is still being displayed with the keyboard cable disconnected, replace the
upper PCA.
27. If you have performed steps 23 - 26 and the STUCK KEY message is still being displayed,
contact Precor customer support for assistance.