IG Power Source Circuit

HEATING / 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 on (IG).

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

WIRING DIAGRAM





INSPECTION PROCEDURE

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

PROCEDURE

1. INSPECT FUSE (ECU-IG LH)

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





(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPLACE FUSE (ECU-IG LH)
OK -- Continue to next step.

2. INSPECT A/C 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 according to the value(s) in the table below.

Standard Voltage:





NG -- CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures

3. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)

(a) Disconnect the A/C amplifier connector.





(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





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

4. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.





Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE A/C AMPLIFIER Removal