Compressor Circuit

AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Manual Air Conditioning System): Compressor Circuit
- Compressor Circuit

DESCRIPTION

When the A/C switch is turned on, the magnetic clutch ON signal is sent from the air conditioning amplifier. Then the MG CLT relay turns on to operate the magnetic clutch.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON and turn the Techstream ON.

(c) Select the item below in the Active Test and then check that the compressor magnetic relay operates.

Air conditioning amplifier





OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG -- Continue to next step.

2. INSPECT FUSE (ECU-IG1)

(a) Remove the ECU-IG1 fuse from the instrument panel junction block.

(b) Measure the resistance of the fuse.

Standard resistance:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

3. INSPECT MAGNETIC CLUTCH RELAY (Marking: MG CLT)





(a) Remove the magnetic clutch relay from the engine room No. 1 relay block.

(b) Measure the resistance of the relay.

Standard resistance:





NG -- REPLACE MAGNETIC CLUTCH RELAY
OK -- Continue to next step.

4. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY)





(a) Disconnect the E36 amplifier connector.

(b) Measure the voltage of the wire harness side connector.

Standard voltage:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

5. CHECK AIR CONDITIONING AMPLIFIER (MGC VOLTAGE)





(a) Remove the air conditioning amplifier with its connectors still connected.

(b) Measure the voltage of the connector.

Standard voltage:





NG -- REPLACE AIR CONDITIONING AMPLIFIER
OK -- Continue to next step.

6. CHECK MAGNETIC CLUTCH





(a) Disconnect the B47 magnetic clutch connector.

(b) Connect the battery's positive (+) lead to terminal 3 of the magnetic clutch and the negative (-) lead to the body ground.

OK:

Magnetic clutch is engaged.

NG -- REPLACE MAGNETIC CLUTCH

OK -- REPAIR OR REPLACE WIRE HARNESS (MAGNETIC CLUTCH - ECU-IG1)