IG Power Source Circuit

AIR CONDITIONING: AIR CONDITIONING SYSTEM: IG Power Source Circuit
- IG Power Source Circuit

DESCRIPTION

The main power source is supplied to the A/C amplifier when the engine switch is on (IG).

The power source is used for operating the A/C amplifier and servomotor, etc.

WIRING DIAGRAM







HINT
Start the engine before inspection. Check the IG1 relay or battery if the engine does not start.

PROCEDURE

1. INSPECT FUSE (ECU-IG RH)

(a) Remove the ECU-IG RH fuse from the cowl side junction block RH.

(b) Measure the resistance of the fuse.

Standard resistance:





NG -- CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE
OK -- Continue to next step.

2. INSPECT AIR CONDITIONING AMPLIFIER (IG+ - GND)





(a) Remove the A/C amplifier with its connectors still connected.

(b) Turn the engine switch on (IG).

(c) Measure the voltage of the connector.

Standard voltage:





NG -- CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BATTERY)

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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





(a) Disconnect the K52 A/C 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.

4. CHECK WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND)





(a) Disconnect the K52 A/C amplifier connector.

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

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE AIR CONDITIONING AMPLIFIER