TM 9-4120-357-14
TABLE 4-2. TROUBLESHOOTING (Cont)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
WARNING
Disconnect power from the air conditioner before doing maintenance work on the
electrical system. The voltage used can be lethal.
Step 4. Check wiring connections to evaporator fan motor, relay K8, and connector plugs for looseness.
Tighten loose connections.
Step 5. Disconnect plug, P15, from motor connector. Using an ohmmeter or continuity tester check
terminals A-B, B-C, C-A, and A, B and C to motor frame or common ground. Continuity should
be indicated on terminal-to-terminal check, but should not be indicated between terminals and
ground.
Replace defective motor.
8. UNIT FAILS TO HEAT.
WARNING
Hearing protection must be worn when maintenance is performed while air condi-
tioner is in operation. Failure to heed this warning can result in hearing loss or in-
jury.
Step 1. Check mode selector switch for incorrect setting.
Set selector switch to LO HEAT or HI HEAT.
Step 2. Make sure that temperature control thermostat is set properly.
Set switch at INCREASE.
Step 3. Inspect for dirty or obstructed air filters.
Clean filters.
Step 4. Remove top, and check for dirty or obstructed mist eliminator.
WARNING
Disconnect power from the air conditioner before doing maintenance work on the
electrical system. The voltage used can be lethal.
Step 5. With top cover removed, check electrical connections to heating element and thermostat, and
visually check elements for damage.
Tighten loose connections. Replace damaged elements.
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