HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS) > Diagnostics for A/C System Malfunction > A/C OR SELF-DIAGNOSIS SYSTEMS DO NOT OPERATE

HVAC SYSTEM (AUTO A/C) (DIAGNOSTICS) > Diagnostics for A/C System Malfunction

A/C OR SELF-DIAGNOSIS SYSTEMS DO NOT OPERATE

TROUBLE SYMPTOM:

• Set temperature is not indicated on the display, switch LEDs are faulty and switches do not operate.

• Self-diagnosis system does not operate.

WIRING DIAGRAM:

STEP	CHECK	YES	NO
1.CHECK FUSE. 1) Turn the ignition switch to OFF. 2) Remove the fuse No. 7, No. 22 and No. 31 from fuse & relay box. 3) Check the condition of fuse.	Is the fuse blown out?	Replace the fuse.
2.CHECK A/C CONTROL MODULE POWER CIRCUIT. 1) Remove the A/C control panel. 2) Disconnect the A/C control panel harness connector. 3) Turn the ignition switch to ACC, and measure the voltage between A/C control panel harness connector terminal and chassis ground. Connector & terminal (i88) No. 15 (+) — Chassis ground (−):	Is the voltage 10 V or more?		Check for open or short circuit in the harness between A/C control panel and fuse.
3.CHECK A/C CONTROL MODULE POWER CIRCUIT. Measure the voltage between A/C control panel harness connector terminal and chassis ground after turning the ignition switch to ON. Connector & terminal (i88) No. 32 (+) — Chassis ground (−):	Is the voltage 10 V or more?		Check for open or short circuit in the harness between A/C control panel and fuse.
4.CHECK A/C CONTROL MODULE GROUND CIRCUIT. Measure the resistance of harness between A/C control panel and chassis ground after turning the ignition switch to OFF. Connector & terminal (i88) No. 34 — Chassis ground:	Is the resistance less than 10 Ω?		Repair the harness for ground line.
5.CHECK POOR CONTACT. Check poor contact of auto A/C control module connector.	Is there poor contact of connector?	Repair the connector.	Replace the auto A/C control module.