Precor 9.21 User manual

9.21, 9.21i, 9.21S, 9.21Si Treadmill
Page 1
9.21, 9.21i, 9.21s, 9.21si Treadmill
Warning: This service manual is for use by Precor trained service providers only.
IfyouarenotaPrecorTrainedServicer,youmustnotattempttoserviceanyPrecorProduct;
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.
© 2003 Precor Incorporated
Unauthorized Reproduction and Distribution Prohibited By Law

9.21, 9.21i, 9.21S, 9.21Si Treadmill
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Section One - Things You Should Know
About This Appendix
Section One, Things You Should Know. This section includes technical specifications and a
procedure matrix. Read this section, as well as the 9.21, 9.21i, 9.21S, 9.21Si Treadmill Owner’s
Manual, before you perform the maintenance procedures in this manual.
Section Two, Software Features. Precor’s 9.21, 9.21i, 9.21S, 9.21Si Treadmill is 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,Wiring and Block Diagrams. This section includes wiring and block diagrams
for 9.21, 9.21i, 9.21S, 9.21Si Treadmill.
General Information
For the latest exploded view, part number and part pricing information, visit the Precor dealer
website at “www.precor.com/Dealer”.

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Technical Specifications
PHYSICAL SPECIFICATIONS
Length: 67 inches (170 cm)
Width: Handrails 28.5 inches (71 cm)
Base 25 inches (63.5)
Height: 44 inches (117 cm)
Running surface: 51 inches by 17 inches (129.5 cm by 43 cm)
Motor: 1.7 hp continuous duty (9.21 & 9.21S)
2.0 hp continuous duty (9.21i & 9.21Si)
Speed: 0.5 to 10 mph (0.8 to 16 kph)
10 mph is equivalent to a 6 minute mile
Incline: 0 to 15% grade
Power: 50/60Hz 120v AC 20 Amps
Weight: 193 lbs (87 kg)
Shipping weight: 233 lbs (105 kg)
ELECTRONIC SPECIFICATIONS
9.21 & 9.21i Programs:
Manual
Interval (1 minute rest: 1 minute work)
Weight Loss
9.21S & 9.21Si Programs:
Heart Rate Interactive Course
Manual
Interval (1 minute rest: 1 minute work)
Weight Loss
6 Preprogrammed courses (3 Walk, 3 Run)
2 Custom courses
9.21, 9.21i, 9.21S & 9.21Si Display Readouts:
Distance (miles or kilometers)
Time
Speed (mph or kph)
Calories
Incline
Heart rate
Scan

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Procedure 2.1 - Accessing the Diagnostic Program
(prior to July 21, 1997)
The 9.21, 9.21S diagnostic program cycles through the following modes:
Software Version Mode. Displays the PROM version number.
LED Mode. Illuminates each of the LED’s mounted on the upper PCA.
Lift Mode. Allows you to verify that the lift calibration number increments and decrements as the
INCLINE keys are pressed.
Power Bits Mode. Allows you to verify that the power bits number increments and decrements
as the SPEED keys are pressed.
Note:
When the treadmill is in power bits mode and the SPEED ▲key is selected, the treadmill speed
will increase twice as fast as it does when the treadmill is in a normal operating mode.
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
Note:
Diagram 2.1 illustrates the 9.21 Treadmill display. The 9.21S Treadmill display is shown in
Diagram 2.2.
2. Press and hold the STOP, SPEED ▼, SPEED ▲and QUICK START keys simultaneously.
3. The electronic console displays the version number of the PROM mounted on the upper
PCA. Record the PROM version number.
4. Following the version number, a horizontal line sweeps from top to bottom and then a
vertical line sweeps from right to left.
Note:
The lines check the LED’s mounted on the upper PCA. If the lines are broken when they sweep
across the electronic console, replace the upper PCA as described in Procedure 5.2 of the
Residential Treadmill Service Manual.
5. After the LED test, the electronic console displays the potentiometer increment number.
6. Press the INCLINE keys. Verify that the running bed inclines and declines as the INCLINE
keys are pressed.
7. Watch the electronic console. When the potentiometer increment number is displayed on
the electronic console, enter power bit mode by starting the running belt.

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Note:
When the running belt is started, the number of power bits will be displayed. Power bits are
directly related to the drive motor input signal.
8. Press the SPEED ▲ and ▼keys. Verify that the power bits number increments and
decrements as the SPEED keys are pressed.
9. Press STOP to return to the Enter Your Weight banner.
10. Turn off the treadmill with the circuit breaker, then unplug the treadmill from the wall outlet.
Diagram 2.1 - 9.21 Display

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Diagram 2.2 - 9.21S Display

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Procedure 2.2 - Accessing the Diagnostic Program (after
July 20, 1997)
Units built after July 20, 1997 used the standard access codes. The keys on the display are
hypothetically numbered for 1 to 7 from left to right. Therefore, ENTER would be key 1, INCLINE
▼ would be key 2, etc. (see Diagram 2.1or 2.2) or on a 9.21i or 9.21Si INCLINE ▲ would be key
1, INCLINE ▼ would be key 2, etc. (see Diagram 2.3).
Placing the unit in the diagnostic mode causes the software to perform the following operations:
a. Test the LED’s mounted on the upper PCA;
b. Provide the option of calibrating the lift system;
c. Display the drive motor power bits;
d. Display and test the heart rate function;
e. Display the error code log;
f. Provide a method of checking the operation of the keys on the electronic console;
g. Test the circuit breaker trip function.
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. Press keys RESET,5,1,7,6,5,7,6,1, sequentially.
3. Following the version number, a horizontal line sweeps from top to bottom and then a
vertical line sweeps from right to left.
Note:
The lines check the LEDs mounted on the upper PCA. If the lines are broken when they sweep
across the electronic console, replace the upper PCA.
4. After the LED test, the electronic console displays the potentiometer increment number.
5. Press the INCLINE keys. Verify that the running bed inclines and declines as the INCLINE
and DECLINE keys are pressed.
6. Watch the electronic console. When the potentiometer increment number is displayed on
the electronic console, enter power bit mode by starting the running belt.

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Note:
When the running belt is started, the number of power bits will be displayed. Power bits represent
the amount of power applied to the drive motor. Power bits are the product of selected speed and
applied load.
7. Press the SPEED ▲ and ▼keys. Verify that the power bits number increments and
decrements as the SPEED keys are pressed.
8. Press the STOP key to exit the power bits mode and enter the heart rate mode.
9. If the heart rate option has been installed, you may test the heart rate function using a chest
strap transmitter or test transmitter.
10. Press the ENTER key to enter the error code log. The error code log will display the last 10
errors that occurred. Error 1 will be the most recent error and error 10 will be the oldest
error. If more than 10 errors occur, the most recent error will be inserted in position 1 and all
other errors will be pushed down one position. The error that was in the 10th position will be
lost. If you wish to clear the error code log, press the QUICK START and STOP keys,
simutaneously.
11. Press the ENTER key to exit the error code log and enter the key pad test.
12. Press each key one at a time the display will confirm the key that was pressed. Press the
INCLINE▼and SPEED ▲ keys, simultaneously to exit the keypad test.
13. The next test is the circuit breaker test. Follow the instructions on the display to cause either
a test trip of the treadmill circuit breaker or exit the diagnostics program.
Diagram 2.3 - 9.21i and 9.21Si Display

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Procedure 2.3 - Displaying the Odometer
(prior to July 21, 1997)
This procedure allows you to display the number of miles or kilometers logged on the treadmill.
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker.
2. With the Enter Your Weight banner scrolling, press the STOP key, the SPEED ▼key, and
then the SPEED ▲key sequentially
Note:
After you perform Step 2, the electronic console displays the number of miles or kilometers
logged on the treadmill.
3. Turn off the treadmill with the circuit breaker, then unplug the treadmill from the wall outlet.

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Procedure 2.4 - Displaying the Odometer
(after July 20, 1997)
The diagnostic program used prior to July 21, 1997 and the diagnostic program used after July
20, 1997 are essentially the same except that the key strokes used to access the programs are
different. Units built after July 20, 1997 used the standard access codes. The keys on the display
are hypothetically numbered for 1 to 7 from left to right. Therefore, ENTER would be key 1,
INCLINE ▼ would be key 2, etc. (see Diagram 2.1) or on a 9.41Si INCLINE ▲ would be key 1,
INCLINE ▼ would be key 2, etc. (see Diagram 2.2).
This procedure allows you to display the number of miles or kilometers logged on the treadmill.
Procedure
1. Plug the power cord into the wall outlet, then turn on the treadmill with the circuit breaker
2. Press keys RESET,6,5, sequentially.
3. The software version will be displayed. Press the ENTER key to continue.
4. The console displays the number of miles logged or kilometers on the treadmill.
5. Turn off the treadmill with the circuit breaker, then unplug the treadmill from the wall outlet.