Heater Relay Circuit

AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System): Heater Relay Circuit

Heater Relay Circuit

DESCRIPTION

The heater relay is turned on by signals from the A/C amplifier. It supplies power to the blower motor controller.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK FUSE (HTR)
(a) Remove the HTR fuse from the driver side J/B.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE FUSE
OK -- Continue to next step.
2. CHECK FUSE (HTR)
(a) Remove the HTR fuse from the engine room J/B.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:





NG -- REPLACE FUSE
OK -- Continue to next step.
3. INSPECT HEATER RELAY





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





NG -- REPLACE HEATER RELAY
OK -- Continue to next step.
4. INSPECT AIR CONDITIONING AMPLIFIER





(a) Disconnect the connector from the A/C amplifier.
(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.
5. CHECK HARNESS AND CONNECTOR (A/C AMPLIFIER - BATTERY)





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





NG -- REPLACE AIR CONDITIONING AMPLIFIER
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE