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 ignition switch is turned to ON.
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 (HTR-IG)




(a) Remove the HTR-IG fuse from the main body ECU.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE FUSE
OK -- Continue to next step.
2. INSPECT AIR CONDITIONING AMPLIFIER (IG+ - GND)




(a) Remove the A/C amplifier with the connectors still connected.
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:





(d) Reinstall the A/C amplifier.
NG -- CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BATTERY)
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
3. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BATTERY)




(a) Disconnect the C8 A/C amplifier connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:





(c) Reconnect the A/C amplifier connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - BODY GROUND)




(a) Disconnect the C8 A/C amplifier connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(c) Reconnect the A/C amplifier connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE AIR CONDITIONING AMPLIFIER