TM 10-3930-675-24-1
TROUBLESHOOTING PROCEDURES (NON-ERROR CODE) - CONTINUED
0007 00
Table 2. Electrical Troubleshooting Procedures (Non-Error Code) - Continued.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
19. Heater/Defroster Producing Low or No Heat. 1. Check operating temperature a. Perform proper PMCS for
of engine.
coolant system (TM 10-3930-
675-10).
b. Warm engine to proper
operating temperature (TM
10-3930-675-10).
2. Inspect the two heater hoses a. Straighten any kinked hoses
between the cab and chassis for
(WP 0190 00).
kinks.
b. Replace any damaged hoses or
kinked hose that will not
straighten (WP 0190 00).
3. Check operation of blower If blower not functioning,
(TM 10-3930-675-10).
perform troubleshooting
procedure for "Blower Motor Not
Working" in this work package.
4. Check operation of heater a. Replace damaged or binding
temperature control switch and
heater temperature control
heater/defroster
selection
switch (WP 0073 00).
switch operation (TM 10- b. Replace damaged or binding
3930-675-10). See step 5
heater/defroster
selection
before replacing any switch.
switch (WP 0073 00).
5a. Remove kick panel from in
a. Replace bent or kinked control
front of the steering column.
cable (WP 0073 00 and WP
Check the operation of the
0191 00).
heater control valve and cable b. Replace damaged, leaking, or
(WP 0191 00).
non-operational heater control
valve (WP 0191 00).
c. Correct any binding of air flow
door and cable.
5b. Check operation of the air
flow door while operating the
heater/defrost selection
switch.
6. Check ducts. With the kick Repair or replace any damaged or
panel removed, check the air separated ducts.
conditioning ducts for any
damage or separations.
7. Check airflow through heater If air flow is very low through
core.
heater core, perform A/C system
maintenance (WP 0265 00).
0007 00-49
