Tennant 235E, Operator'S Manual

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MAINTENANCE
3-17
235E MM165 (3--93)
PROPELLING SYSTEM TROUBLESHOOTING
Problem Cause Verification/Remedy
No propelling Low battery charge Charge batteries No propelling
Loose or broken wires Locate and fix or replace wires
Controller overheated (for
machines below serial number
002311)
Thermal switch tripped -- allow
controller time to cool down
Blown fuse (80A) Replace fuse
Seat shroud switch failure Replace seat shroud switch
Key-operated on-off switch failure Replace on-off switch
Motor or gearbox failure Check motor and gearbox for
binding. Check motor for failure
M3 contactor failure Replace M3 contactor
Vehicle accelerates without
pedal movement
Directional pedal not at “neutral”
position
See PROPELLING CIRCUIT : TO
ADJUST “NEUTRAL”POSITION
Full speed only Damaged wires, short circuits,
crossed wires
Check visually for damage Check
controller for dirt or metal chips
causing short circuit
Machine will not reach full
speed
Batteries run down Charge batteries
Vibration or roughness when
braking
M1 and M2 contactor failure Replace M1 and M2 contactor
Weak and uneven braking
forward and reverse
M1 and M2 contactor failure Replace M1 and M2 contactor
Very strong braking Armature and field wires
interchanged
Correct wire installation
Contactors close, little or no
power. High pitched whistle
Loose connections Locate and fix or replace wires Contactors close, little or no
power. High pitched whistle
Short circuit in motor Test for short circuit. Repair or
replace
Armature and field wires
interchanged
Correct wire installation
Contactors close, machine
moves to full speed but lacks
power
Loose connections Locate and fix or replace wires
Forward speed only Contactor failure Replace contactor
Reverse speed only Contactor failure Replace contactor
Sporadic operation Low battery charge Charge batteries Sporadic operation
Controller overheated (for
machines below serial number
002311)
Thermal switch tripped -- allow
controller time to cool down
Water in circuit Disconnect batteries and dry
affected areas
NOTE: For more detailed troubleshooting information for qualified personnel, order the 235E Propelling
System Troubleshooting Manual, TENNANT part number MM182.