Mitsubishi 3000GT Service Manual page 1276

FULL AUTO AIR CONDITIONING - Troubleshootina
No.
Symptom
Air conditioning does
not operate when the
ignition switch in the
ON position.
Interior temperature
does not raise
Interior temperature
Probable cause
Open-circuited power circuit harness / Correct harness.
Defective control panel
Defective air conditioning control unit
Defective magnetic clutch relay in
relay box
Defective magnet clutch
Defective thermostat
Defective A/C engine coolant tem-
perature switch for air conditioning
cut off <Up to 1993 models>
Defective dual pressure switch
Refrigerant leak
Excessive refrigerant
Defective A/C compressor lock con-
troller <DOHC>
Defective MFI control unit
Defective interior temperature sensor
input circuit
Defective blend air damper poten-
tiometer input circuit
Defective blend air damper drive mo-
tor
Incorrect engagement of blend air
damper drive motor lever and blend
air damper
Sticking blend air damper
Open-circuited harness between
blend air damper drive motor and air
conditioning control unit
Defective control panel
Defective air conditioning control unit
Defective interior temperature sensor
input circuit
Defective air inlet sensor input circuit
Defective air therm0 sensor input cir-
cuit
Defective blend air damper poten-
tiometer input circuit
TSB Revision
Check on-board diagnos-
tic output.
Replace.
Replace.
Replace.
Replace.
Replace.
Charge refrigerant, cor-
rect leak.
Discharge refrigerant.
Replace A/C compressor
lock controller.
Replace MFI control unit.
Check on-board diagnos-
tic output.
Replace defective parts.
Replace blend air damper
drive motor.
Engage correctly.
Correct blend air damper.
Correct harness.
Replace air conditioning
control unit.
Check on-board diagnos-
tic output.
Replace defective parts.
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1
Ref. page
5 5-73
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55-69
55-29
55-73
55-73
55-69