Electrical Troubleshooting - MacDon M155 Operator's Manual

6.2 Electrical Troubleshooting

Symptom Problem
Defective battery
Loose or corroded
connections
Low voltage and/or Defective alternator belt
battery will not
charge
Alternator or voltage regulator
not connected properly
Dirty or defective alternator,
defective voltage regulator, or
high resistance in circuit
Defective light switch
Lights dim
High resistance in circuit or
poor ground on lights
Burned out or defective light
bulb
Lights do not light
Broken wiring
Poor ground on lights
Open or defective circuit
breaker
Defective relay
Defective light switch
Turn signals or
indicators showing Reversed wires
wrong direction
Broken or disconnected wire
Circuit breaker tripped
No current to cab
Battery disconnect switch is
OFF
147649
TROUBLESHOOTING
Solution
Have battery tested.
Clean and tighten battery connections.
Replace worn belt.
Connect properly.
Contact Dealer.
Check the wiring circuit for a break in
a wire or a poor ground.
Replace light bulb.
Check wiring for broken wire or shorts.
Clean and tighten ground wires.
Check circuit breaker
Replace relay
Contact Dealer
Contact Dealer
Contact Dealer
Breaker automatically resets.
Turn battery disconnect switch ON.
435
Section
Battery, page 369
Maintaining the
Battery, page 369
Replacing Fan
Belt, page 365
Replacing Fan
Belt, page 365
Battery, page 369
Contact Dealer
—
Replacing
Headlight Bulb,
page 378
Replacing Bulb
in Cab-Forward
Flood Light, page
381
Replacing Bulb in
Rear Flood Light,
page 386
—
Accessing Circuit
Breakers and
Fuses, page 396
Replacing Circuit
Breakers and
Relays, page 397
Contact Dealer
Contact Dealer
Contact Dealer
—
Battery Main
Disconnect Switch,
page 369
Revision A