Circuit Breakers and Relays (Engine Compartment)

Circuit breakers will trip and remain open as long as an overload or short exists. To reset, turn key off and allow circuit breakers to cool.

NOTE: Lighting system circuit breakers (B) and (D) are serviced as an assembly. If replacement is necessary, change the complete assembly.

Circuit breakers protect the main power cable for the electrical system, lighting system assembly, cab air control system and the auxiliary power outlet system in the cab. If a breaker does not reset, replace it. If it does reset and trips again, determine cause and correct.

Relays (J) and (L) carry large electrical loads and are controlled by the ignition switch.

Removal and installation of all circuit breakers and relays are similar. Torque large nuts to specification.

Specification

Large Nuts -Torque 3.4 +/-0.6 n·m (30 lb-in.)
Tighten small nuts to specification.

Specification

Small Nuts -Torque 2.5 +/- 0.5 n·m (22 lb-in.)

H57454


A-F1 A/C System Circuit Breaker
B-F2 Lighting System Breaker 1
C-F3 Service Light Circuit Breaker
D-F4 Lighting System Breaker 2
E-F5 Ignition System Power Breaker
F-F6 Auxiliary Power Strip Breaker 1
G-F7 Control Circuit Power Breaker
H-F8 Auxiliary Power Strip Breaker 2
I-F9 Engine Control Unit Circuit Breaker
J-K1 A/C System Relay
K-K2 Service Light Relay
L-K3 Run Relay

AG,OUO1035,1569 -19-24JAN00-1/1