Precor TRM 811.v2, Service Manual

Page: 70 / 114

© Precor Incorporated, Unauthorized Reproduction and Distribution Prohibited by Law Page 70
4. Verify the wiring of the HHHR contacts (top left, bottom left, top right, bottom right) go to the
proper pin on the Grip/Contact connector, that none of the lines are shorted,

If NO, Correct the wiring error.

If Yes, Continue.
5. Verify that the grip connections are free of corrosion.

If NO, Replace the corroded HHHR grips.

If Yes, Continue.
6. Verify that the unit does not display a heart rate with only one hand on a grip. This would
indicate static damage, and require replacement of the heart rate board.
7. If the above procedures do not correct the problem, replace the heart rate board.
Figure 17: Hand Held - Chest Strap Heart Rate PCA
Wireless Heart Rate Does Not Work
1. Verify wireless heart rate with a known good chest strap transmitter or test transmitter. If the
heart rate reading is erratic, incorrect, or absent, continue with step 2.
NOTE: It may be necessary to lean in closer to the console at first to allow receiver to
begin to acquire a heart rate signal.
2. Verify that the HHHR board has the correct operating voltage. Connect a voltmeter to VCC
and Ground on the Power/Signal connector. The voltage should read between 4.5 and
5.5VDC.
3. Identify other sources of wireless interference signals in close proximity to the unit (such as
Wi-Fi networks, cordless phones, etc.).
NOTE: This is not to say that something like a Wi-Fi network cannot be present at all, but
if it is transmitting in close proximity to the treadmill the heart rate system MAY pick it up.
These interference sources can be very difficult to track down and locate, and may
require that you ask the customer if such devices are present. Some common sources of
interference signals are listed below.