Precor C960 Service Manual page 41

14. If a hand held signal was accepted in step 13, the hand held contact wiring is reversed. The
end of the wire harness that connects to the hand held contacts in the handlebar is
segregated into two groups. One group has blue shrink wrap around it and the other group
has black shrink wrap around it. The "blue" group must go to the right hand contacts and the
"black" group must go to the left hand contacts. In both groups the black wire must go to the
lower contact and the red wire must go to the upper contact. If necessary, rewire the hand
held contacts as described above and test as described in step 6.
15. Set the on/off switch in the "off" position. Refer to Diagram 5.3 for the following
measurements. With an ohmmeter measure between the "lower right contact" pin on the J1
connector and the lower right hand held heart rate contact on the handlebar. The reading
should be 1 W or less. Measure between the "upper right contact" pin on the J1 connector
and the upper right hand held heart rate contact on the handlebar. The reading should be 1
W or less. Measure between the "upper left contact" pin on the J1 connector and the upper
left hand held heart rate contact on the handlebar. The reading should be 1 W or less.
Measure between the "lower left contact" pin on the J1 connector and the lower left hand
held heart rate contact on the handlebar. The reading should be 1 W or less. If any of the
above readings are greater than 1 W, replace the heart rate PCA to handlebar wire harness.
No hand held reading - No chest strap reading
16. Set the on/off switch in the "on" position and access the diagnostic program (Procedure 2.1
or 2.2). Advance to the heart rate display portion of the diagnostic program. Verify that
neither a chest strap signal or a hand held signal is being accepted with either a heart rate
test transmitter or a chest strap transmitter.
17. Check the plug/connector connections on both the heart rate PCA (J4), and upper PCA (J1).
18. If neither a chest strap signal or a hand held signal is being accepted, measure between the
"ground" and "5 Vdc" pins on J4 for 5 Vdc. If 5 Vdc is present, replace the heart rate PCA.
19. If 5 Vdc is not present, remove the connector from J4 of the heart rate PCA. Measure
between the "ground" and "5 Vdc" pins of the connector (just removed from the heart rate
PCA) for 5 Vdc. If 5 Vdc is present, replace the heart rate PCA. If the 5 Vdc is not present,
measure between the corresponding pins of J1 on the upper PCA (red and black wires). If 5
Vdc is not present replace the upper PCA. If 5 Vdc is present, replace the upper PCA to
heart rate PCA cable.
Constant or intermittent readings when neither the hand held or chest strap is in use
20. Verify that a ferrite core is clamped around the heart rate PCA to upper PCA cable.
21. Constant or intermittent heart rate readings when neither heart rate system is in use is
caused by something in the near vicinity radiating RF energy that is being received by the
chest strap portion of the heart rate PCA.
22. Temporarily, install a spare jumper on J14 of the heart rate PCA (hand held priority). Set the
on/off switch in the "on" position and repeat the procedure in step 6.
C960 Series Commercial Treadmill
Page 41