IG Power Source Circuit

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 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 according to the value(s) in the table below.
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 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 WIRE HARNESS (AIR CONDITIONING AMPLIFIER - BODY GROUND)





(a) Disconnect the A/C amplifier connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE AIR CONDITIONING AMPLIFIER