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TROUBLESHOOTING
6.2
Electrical Troubleshooting
Symptom
Problem
Solution
Section
Defective battery
Have battery tested.
Battery, page 369
Loose or corroded
connections
Clean and tighten battery connections.
Maintaining the
Battery, page 369
Defective alternator belt
Replace worn belt.
Replacing Fan
Belt, page 365
Replacing Fan
Belt, page 365
Alternator or voltage regulator
not connected properly
Connect properly.
Battery, page 369
Low voltage and/or
battery will not
charge
Dirty or defective alternator,
defective voltage regulator, or
high resistance in circuit
Defective light switch
Contact Dealer.
Contact Dealer
Lights dim
High resistance in circuit or
poor ground on lights
Check the wiring circuit for a break in
a wire or a poor ground.
—
Replacing
Headlight Bulb,
page 378
Replacing Bulb
in Cab-Forward
Flood Light, page
381
Burned out or defective light
bulb
Replace light bulb.
Replacing Bulb in
Rear Flood Light,
page 386
Broken wiring
Check wiring for broken wire or shorts.
Poor ground on lights
Clean and tighten ground wires.
—
Open or defective circuit
breaker
Check circuit breaker
Accessing Circuit
Breakers and
Fuses, page 396
Defective relay
Replace relay
Replacing Circuit
Breakers and
Relays, page 397
Lights do not light
Defective light switch
Contact Dealer
Contact Dealer
Turn signals or
indicators showing
wrong direction
Reversed wires
Contact Dealer
Contact Dealer
Broken or disconnected wire
Contact Dealer
Contact Dealer
Circuit breaker tripped
Breaker automatically resets.
—
No current to cab
Battery disconnect switch is
OFF
Turn battery disconnect switch ON.
Battery Main
Disconnect Switch,
page 369
147649
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Revision A
Summary of Contents for M155
Page 3: ...Declaration of Conformity Figure 1 Declaration of Conformity Page 1 of 2 147649 i Revision A ...
Page 4: ...Figure 2 Declaration of Conformity Page 2 of 2 147649 ii Revision A ...
Page 30: ...SAFETY Figure 1 21 Safety Signs Left Cab forward Side 147649 14 Revision A ...
Page 32: ...SAFETY Figure 1 23 Safety Signs Right Cab forward Side 147649 16 Revision A ...
Page 44: ......
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Page 320: ......
Page 414: ...MAINTENANCE AND SERVICING Fuse Box Decal Figure 5 178 Fuse Decal 147649 398 Revision A ...
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