3-24. ACCESSORIES TROUBLESHOOTING (CONT)
TEST OR INSPECTION
7. COLD AIR BLOWN FROM CAB HEATER (Cont) .
S t e p 2 . ( C o n t ).
a. If heater turnoff valves are closed, open.
b. If heater turnoff valves are open, go to step 3 below.
Check if area around console is obstructed, preventing flow of air
through and around heater core.
a . I f
b . I f
Step 4. Remove
8. DEFROSTER MOTOR
obstructions seen, remove.
obstructions are not seen,
and test engine thermostat
engine thermostat does not
go to step 4 below.
test okay, replace (page 4-87).
engine thermostat tests okay, remove and replace HEAT CONTROL
located on cab switch panel (page 10-46).
DOES NOT OPERATE.
Step 1. Turn ignition key switch to on position.
Pull HEATER FAN switch on cab switch panel out.
Check if heater fan is on.
a. If heater fan is not on, go to step 2 below.
b. If heater fan is on, go to step 5 below.
Press 5 ampere circuit breaker located on right instrument p a n e l.