Hyster-Yale Electric Pallet Truck MSW020-E

REPAIR: A proximity switch is used to sense the position of the control handle arm.

Move the lift truck to a safe, level area before performing any repairs.

Turn the key switch to the OFF position.

Remove the upper drive unit compartment cover.

Remove the lower drive unit compartment cover.

Remove the four capscrews from the two-piece shield over the MDU and remove the shields.

Turn the key switch to the ON position.

Verify battery voltage at the proximity switch connector between pin #1 and pin #2.

Move lift truck to a safe, level area.

Turn the key switch to the OFF position and disconnect battery connectors.

Block drive tire to prevent movement.

Remove the upper drive unit compartment cover.

Discharge the capacitor. See Special Precautions.

Tag, identify, and disconnect the contactor coil wires.

Test contactor coil using an ohmmeter.

Touch the probes of the ohmmeter to the coil terminals and measure the resistance between the terminals.

Replace contactor if coil resistance readings measure outside of specifications.

NOTE: On some models, the dash indicator will display the code: EP 107 (or a higher number) for 1 to 2 seconds every time the key switch is turned to the ON position. This code represents the EEPROM software version and DOES NOT INDICATE A FAULT CODE.

NOTE: These checks require a volt-ohmmeter. Specific checks require additional equipment.

NOTE: The correct meter polarity is necessary for the checks. The voltage checks are made between the individual points and battery negative. Connect the meter negative to battery negative.

Block lift truck so the drive wheels are off the floor. See the section Periodic Maintenance 8000YRM1048, Periodic Maintenance 8000YRM1009, or Periodic Maintenance 8000YRM1379 lift trucks. Refer to How to Put a Lift Truck on Blocks.

Turn the key switch to the OFF position.

Disconnect and separate the battery connectors.

Remove the upper drive unit compartment cover.

Remove the lower drive unit compartment cover.

Discharge the capacitor. See Special Precautions.

CAUTION: The pinion end cover and the armature are heavy components. Work carefully so the field coils, pole pieces, and armature are not damaged during disassembly and assembly.

Remove the traction motor and brake assembly from the MDU

Clean outside surfaces of motor before disassembly

Make index marks on the ends of the motor and field ring to ensure proper reassembly

Measure the brush in the brush holder

Remove capscrews from commutator end of motor

Carefully slide end cover from motor and armature shaft

Remove screws that fasten pinion end cover to field ring

Warning: This procedure requires trained personnel with PPE!

Lift truck moved to a safe, level area

Drive tire blocked to prevent movement

Key switch turned to the OFF position and battery connectors disconnected

Upper drive unit compartment cover removed

Wires and cables tagged, identified, and disconnected

All wires and cables disconnected from the contactor

Two mounting screws and lockwashers that hold contactor to plate loosened and contactor removed