Taylor-Dunn MX-026-00, Operation, Maintenance, And Replacement Parts Manual

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Curtis PMC Troubleshooting
Page 29
MOTOR
High motor current in both the field and the armature, accompanied with a lack of power, would
indicate a shorted armature and\or field.
Another symptom that may exist is jumping or stuttering at low speeds and/or the motor will
not run unless the armature is manually rotated. If this symptom exists, it indicates that there
may be open segments in the armature. Visually inspect the brushes, if they are OK, continue
with the testing below.
Disconnect the four motor wires and perform the following tests:
Check continuity from ‘A1’ to the frame of the
motor..
If you do not know how to test for continuity, refer
test to a qualified technician.
•
This should be an open circuit. If there
is continuity from ‘A1’ to the frame of
the motor, then the motor armature or
armature circuit (brushes) are shorted.
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, otherwise
continue with the next test.
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.