|
| |
TM 9-4120-389-14
Table 4-2. UNIT TROUBLESHOOTING-(cont.)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 2.
Check operation of heater cut-out switch (S3). Test switch (See para. 4-57).
Replace if defective.
Step 3.
Check operation of mode selector switch (S1). Test switch. (See para. 4-41).
Replace if defective.
7.
HEAT IN HI HEAT MODE, BUT NOT IN LO HEAT MODE.
Step 1
Check for loose or damaged electrical connectors, or damaged wires in wiring harnesses.
WARNING
Disconnect input power before performing internal electrical troubleshooting.
Voltages used can be deadly.
Tighten or replace loose or damaged connectors, or repair damaged wires.
Step 2.
Check operation of heater relays (K2 and KS). Test relays. (See para. 4-49). Replace
relays if defective.
Step 3.
Check operation of Temperature control switch (S2).
a.
Inspect sensing bulb and capillary for damage or leakage. (See para. 4-43).
Replace entire temperature control switch if bulb is damaged or leaking.
b.
Test switch in Temperature selector. (See para. 4-43). Replace entire control, if defective.
4-57
|
