A/C Signal Circuit Troubleshooting (Climate Control System)
A/C Signal Circuit TroubleshootingNOTE:
- Do not use this troubleshooting procedure if any of the following items are operative, A/C condenser fan, radiator fan, A/C compressor Refer to the symptom troubleshooting index Symptom Related Diagnostic Procedures
- Before performing symptom troubleshooting, check for powertrain DTCs.
1. Check for body DTCs using B-CAN system diagnosis test mode A troubleshooting.
Are there any DTCs indicated?
YES - Do the appropriate troubleshooting for the DTC indicated.
NO - Go to step 2.
2. Turn the ignition switch OFF.
3. Disconnect audio-HVAC display panel connector A (22P).
4. Turn the ignition switch ON (II).
5. Measure the voltage between the No. 5 terminal of audio-HVAC display panel connector A (22P) and body ground.
Is there 5 V or more?
YES - Go to step 6
NO - Repair open in the wire between the relay control module panel and the audio-HVAC display panel.
6. Turn the ignition switch OFF.
7. Measure the evaporator temperature sensor resistance between the No. 14 and No. 15 terminals of audio-HVAC display panel connector A (22P).
Is the resistance less than 24 kOhms?
YES - Go to step 8.
NO - Test the evaporator temperature sensor.
8. Reconnect audio-HVAC display panel connector A (22P).
9. Turn the ignition switch ON (II).
10. Check that blower motor operates at all speeds.
Does the blower motor operate at all speeds?
YES - Check for loose wires or poor connections at audio-HVAC display panel connector A (22P) If the connections are good, substitute a known-good audio-HVAC display panel and recheck If the symptom/indication goes away, replace the original audio-HVAC display panel.
NO - Repair the problem in the blower motor circuit.