A/C Signal Circuit Troubleshooting

• 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.
  
• Before performing symptom troubleshooting, check for powertrain DTCs, except K20Z2 engine, K20Z2 engine.
  

1.	Turn the ignition switch OFF.

2.	Disconnect the climate control unit 32P connector.

3.	Turn the ignition switch ON (II).

4.	Measure the voltage between the climate control unit 32P connector terminal No. 6 and body ground.   Is there battery voltage? YES - Go to 5. NO - Repair open in the wire between the climate contro unit and the MICU.n

5.	Turn the ignition switch OFF.

6.	Measure the evaporator temperature sensor resistance between the climate control unit 32P connector terminals No. 8 and No. 19.   Is the resistance less than 24 kW? YES - Go to 7. NO - Test the evaporator temperature sensor.n

7.	Reconnect the climate control unit 32P connector.

8.	Turn the ignition switch ON (II).

9.

Check the blower motor operates at all speeds. Does the blower motor operate at all speeds? YES - Check for loose wires or poor connections at climate control unit 32P connector. If the connections are good, substitute a known-good climate control unit and recheck. If the symptom/indication goes away, replace the original  climate control unit.n NO - Repair the problem in the blower motor circuit.n