A/C Switch System - Mitsubishi Electric Lancer Evolution-VII Workshop Manual

13A-92
Inspection Procedure 26

A/C switch system

When the A/C switch on the control panel is turned ON, the A/C switch ON
signal is input to the engine-ECU. After receiving this signal, the engine-ECU
turns the A/C compressor ON.
Measure at the C-122 engine-ECU
connector.
D Measure the engine-ECU terminal
voltage.
D Engine: Idling
D A/C setting temperature
When room temperature is 25_
or more: Max Cool
When room temperature is 25_
or less: Max Hot
D Voltage between terminal No. 45
and earth
D A/C switch: ON
(A/C compressor driven state)
OK: System voltage
D A/C switch: OFF
OK: 0.5 V or less
OK
Check the following connector: C-122
OK
MUT-II Data list
D No. 28: A/C switch
D Engine: Idling
D A/C setting temperature
When room temperature is 25_
or more: Max Cool
When room temperature is 25_
or less: Max. Hot
D A/C switch: ON
OK: ON
D A/C switch: OFF
OK: OFF
NG
Replace the engine-ECU.
MPI -
Troubleshooting
NG
Check the A/C system. (Refer to
GROUP 55 - Troubleshooting.)
NG
Repair
OK
Intermittent malfunction (Refer to
GROUP 00 - Points to Note for
Intermittent Malfunctions.)
Probable cause
D Control panel A/C switch malfunction
D A/C system malfunction
D Engine-ECU malfunction