9.41S, 9.41Si Treadmill
Page 20
Procedure 5.3 - Troubleshooting the Lift System
System Description
The lift system is powered by a 120 Vac lift motor that uses two independent motors windings,
one operates the motor in an upward direction and one operates the motor in a downward
direction. The motor contains a 10 K
Ω
potentiometer, driven by the motor, that indicates lift
position. AC power to operate the lift motor is provided by a pair of triac. One triac provides
power to the “up” winding of the lift motor and the other triac provides power to the “down”
winding of the lift motor. The triacs are controlled either manually or by software control from the
upper PCA.
1.
If the lift motor will not move skip to step 7. If the lift motor moves and an error occurs
continue with step 2.
2.
Access the diagnostics program per Procedure 3.2 and proceed to the lift calibration portion
of the diagnostics program. If the lift calibration number is 0 or 255 skip to step 3. Operate
the lift, if the lift calibration number does not increment as the lift moves, skip to step 3. If the
calibration number increments as the lift moves, recalibrate the lift per Procedure 5.3. If
recalibration does not correct the problem, continue with step 3.
3.
Set the treadmill circuit breaker in the “off” position. Using an ohmmeter, measure between
terminal 4 (white wire) and terminal 6 (orange wire) of the P2 connector on the lower PCA.
The measurement should be approximately 10 K
Ω
. If the measurement is open (
∞
) or
significantly high or low, replace the lift motor.
4.
Using an ohmmeter, measure between terminals 4 and 5 of P2 and measure between 5 and
6 of P2 on the lower PCA. The two measurements should total approximately 10 K
Ω
. If the
measurement is open (
∞
) or significantly high or low, replace the lift motor.
5.
If you have performed all of the above tests and an error still occurs when the lift motor
operates, there are three parts that could cause the problem. There are not any good tests
to check these parts other than substituting a known good part. They are lower PCA, ribbon
cable and upper PCA. Replace only one part at a time. If the new part does not correct the
problem replace the original part.
6.
If you have performed all of the above tests and the lift system is still not functioning, call
Precor Technical Support.
7.
Set the treadmill circuit breaker in the “off” position. Remove the F2 (2 amp slow blow) fuse
from the lower PCA. Measure the fuse with an ohmmeter. The measurement should be 1
Ω
or less. If the fuse is good, re-insert the fuse and skip to step 9. If the fuse is open (
∞
)or
significantly high, replace the fuse. Before operating the lift motor it is necessary to perform
a continuity test on the lift motor.
