Taylor-Dunn SC-011-59, Operation, T Roubleshooting And Replacement Parts Manual

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ELECTRICAL TROUBLESHOOTING
Special Troubleshooting Page 5
FREEWHEEL DIODE
Remove the wires from the ‘B+’ and ‘M-’
terminals on the PMC control and perform the
following test:
Using the diode test function on the DMM check
for the presence of a diode across ‘B+’ and ‘M-
’ on the PMC control. Refer to Diode Figure 2.
If you do not know how to test for a diode, refer
test to a qualified technician.
•
If the diode is open or shorted, then the
PMC control must be replaced. Stop
trouble shooting here and repair the
problem. When the repair is completed,
completely retest the vehicle before
lowering the drive wheels to the ground.
STOP
Stop, do not continue. If you reached this point without a solution, then you may have an
unanticipated problem or have made an error during testing. It is important to review the
trouble shooting steps that have led to this point. The tests may need to be repeated.
B-
M-
A2
B+
#2
KSI
_
+
The reading shown is for illustration
only. The actual reading may vary.
1. Make sure the key-switch is in the “OFF” position, then remove
the key.
2. Place the forward-reverse switch in the center “OFF” position.
3. Set the park brake.
4. Place blocks under the front wheels to prevent vehicle movement.
5. Disconnect the main positive and negative cables at the batteries.
The rear drive wheels may rotate during some of the following tests.
Block the front wheels, raise the rear drive wheels off the ground,
and support the vehicle with jack stands. Failure to do so may cause
the vehicle to move and cause severe bodily injury and/or property
damage.
Rotating rear drive wheels are a potential hazard. Keep hands, arms,
legs and loose clothing away from the rear drive wheels while
conducting tests. Failure to do so may cause serious bodily injury.