Galant VR4 AWD L4-1997cc 2.0L DOHC Turbo (1992)
A/C Signal: Testing and Inspection
To test the A/C signal, proceed as follows:
Air Conditioning Circuit
1. Start and warm the engine to operating temperature. Turn the blower and A/C to the ON position.
2. Using a Volt meter, check the Voltage between ECU harness terminal 7 and ground.
Voltage ............................................................................................................................................................................................. System Voltage
3. Turn the key to the OFF position and disconnect the negative battery terminal and ECU connector.
4. Using an Ohm meter, check for continuity between ECU harness terminal 7 and harness terminal 1 of the A/C dual pressure switch.
Continuity .............................................................................................................................................................................................. Should exist
5. Using an Ohm meter check for continuity between ECU harness terminal 7 and ground.
Continuity ....................................................................................................................................................................................... Should not exist
NOTE: If the engine temperature is above approximately 238° F, the coolant temperature switch will open the circuit between the A/C control unit
and the ECU.
If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed,
confirm that the repair has corrected the problem.
If the trouble returns, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions
and test for an intermittent failure.
