Heater Control Switch Circuit

HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: Heater Control Switch Circuit
- Heater Control Switch Circuit

DESCRIPTION

The No. 3 heater control sub-assembly is powered through the HTR-IG fuse. The No. 3 heater control sub-assembly transmits operation signals of each switch to the air conditioning amplifier assembly.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedures.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL SUB-ASSEMBLY - BATTERY)

(a) Disconnect the C31 No. 3 heater control connector.





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

Standard Voltage:





Text in Illustration





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

2. INSPECT NO. 3 HEATER CONTROL SUB-ASSEMBLY

(a) Remove the No. 3 heater control sub-assembly Disassembly.

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





Standard Resistance:





(c) Apply battery voltage to the terminals and check that the indicator light comes on.

OK:





NG -- REPLACE NO. 3 HEATER CONTROL SUB-ASSEMBLY Disassembly
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (NO. 3 HEATER CONTROL SUB-ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the C31 No. 3 heater control connector.

(b) Disconnect the C32 amplifier connector.

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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Symptom Related Diagnostic Procedures