Precor 9.31 Manual page 30

No hand held reading - No chest strap reading
11. Access the diagnostic program (Procedure 3.2). 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.
12. Check the plug/connector connections on both the heart rate PCA (J4), and upper PCA
(J1).
13. 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.
14. 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
15. Verify that a ferrite core is clamped around the heart rate PCA to upper PCA cable.
16. 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.
17. Replace the heart rate PCA with a 43579-108 (or higher) heart rate PCA. 43579-108
and higher versions of heart rate PCA are less susceptible to radiated RF energy
9.31, 9.33, 9.35 Treadmill
Page 30