Precor 9.45 Service Manual page 27

3. Set the treadmill circuit breaker in the "off" position. Remove the 2 amp lift fuse (F2) from the
lower PCA. Using an ohmmeter, measure the fuse resistance. The fuse should measure
approximately 1Ω or less. If the fuse is open (∞) or significantly higher than 1Ω, replace the
fuse. If the fuse was bad, perform the test in step 4 before applying power to the lift. If the
fuse was good continue with step 5.
4. Using an ohmmeter, measure the resistance across the lift capacitor terminals. The Lower
PCA resistance should be extremely high (megohms), the capacitor resistance should be
extremely high (megohms) and the lift motor winding should read approximately 34Ω (120
Vac units) or 122Ω (240 Vac units). Therefore, if the measurement is significantly lower than
34Ω or 122Ω, disconnect both red leads from the lift capacitor. Measure the resistance
between the black leads on the lift capacitor and red lead to the lower PCA. If it measures
significantly low, replace the lower PCA. Measure the resistance between the black leads on
the lift capacitor and red lead to the lift motor. If it measures significantly low, replace the lift
motor. Measure the resistance between the black leads on the lift capacitor and other
terminal of the lift capacitor. If it measures significantly low, replace the lift capacitor.
5. At this point the lift fuse is good, but there is no AC voltage on the lift capacitor when the lift
is actuated. There are three potential causes for this condition. They are lower PCA, ribbon
cable or upper PCA. There are no good means of troubleshooting these components other
than substituting known good components. Replace only one component at a time. If the
component that you replaced does not correct the problem, replace the original component.
Try substituting the lower PCA first, the ribbon cable second and the upper PCA third. If you
have performed all of the above procedures and have been unable to correct the problem,
call Precor Customer Support.
6. Using an ohmmeter, measure the resistance across the lift capacitor terminals. The lower
PCA resistance should be extremely high (megohms), the capacitor resistance should be
extremely high (megohms) and the lift motor winding should read approximately 34Ω or
122Ω. If it measures significantly high or open (∞), replace the lift motor.
If the resistance measurement in step 6 was approximately 34Ω (120 VAC units) or 122Ω
7.
(240 VAC units), replace the lift capacitor. If you have performed all of the above procedures
and have been unable to correct the problem, call Precor Customer Support.
8. Typically, when the lift is able to physically move but causes a lift error, the problem is in the
lift position identification system (rotation sensor and zero sense switch).
9. Connect a DC voltmeter between the white wire (term. 2 of J3) and the red wire (term. 4 of
J3) on the lower PCA. Set the treadmill circuit breaker in the "on" position and slowly rotate
the hub at the bottom of the lift motor by hand. The DC voltmeter should read approximately
5 Vdc when the magnet in the hub is not near the hall effect sensor and approximately 0
VDC when the magnet is near the hall effect sensor. If the voltage switches between 5 and
0 Vdc as the magnet passes the hall effect sensor continue with step 11.
9.45, 9.45i Treadmill
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