Yale 524150797

Troubleshooting
PROBLEM POSSIBLE CAUSE PROCEDURE OR ACTION
Unusual noise from traction motor. Parking brake not releasing/
damaged.
Troubleshoot the parking brakes.
Drive unit internal damage. Check that the drive unit rotates
smoothly.
Traction motor bearing damaged. Replace end head(s) and check
stator and rotor for damage. Re-
place damaged components or
traction motor if necessary.
Truck moves slow or in a jerky mo-
tion.
Encoder broken. Replace encoder bearing.
Encoder wire broken. Check and repair encoder wire or
replace encoder bearing.
Temperature sensor failure. Temperature sensor wire dam-
aged.
Measure resistance with ohmme-
ter. Resistance should be 530
ohms at 25 °C (77 °F). Inspect and
repair temperature sensor wire.
The temperature sensor wire can
be repaired, but the temperature
sensor must be replaced if faulty.
Main wiring harness damaged. Test temperature sensor circuit
through main wiring harness from
connection at controller.
Temperature sensor malfunction. Measure resistance with ohmme-
ter. If wiring is ok, resistance
should be 530 ohms at 25 °C (77
°F). Replace the temperature sen-
sor.
Stator shorting. Loss of insulation in wire. Disconnect the battery and check
resistance between winding and
case. Resistance should be at
50,000 ohms or above.
Stator open circuit. Broken coil windings. Raise drive wheel off the floor and
verify voltage at motor terminals.
Disconnect the battery and check
resistance of windings.
Troubleshooting 0620 YRM 1513
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