Heating & A/C System: 73

73-AC REQUEST OUTPUT SIGNAL TOO HIGH





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.

- When Monitored:
With the ignition on.

- Set Condition:
If the A/C Heater Control detects voltage above 4.49 volts on the (C221) A/C Switch Sense circuit.





NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Refer to HVAC System Test (MTC) for stored DTC test procedures. HVAC System Test

1. CHECK (C221) A/C SWITCH SENSE CIRCUIT VOLTAGE AT A/C HEATER CONTROL C1 HARNESS CONNECTOR




1. Turn the ignition off.
2. Disconnect the A/C Heater Control C1 harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (C221) A/C Switch Sense circuit.

Is the voltage above 5.2 volts?

Yes

- Go To 2

No

- Replace the A/C Heater Control.
- Perform the BODY VERIFICATION TEST Body Verification Test.

2. CHECK (C221) A/C SWITCH SENSE CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the Instrument Cluster C3 harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (C221) A/C Switch Sense circuit.

Is the voltage above 0.2 volts?

Yes

- Repair the (C221) A/C Switch Sense circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST Body Verification Test.

No

- Replace the Instrument Cluster (CCN).
- Perform the BODY VERIFICATION TEST Body Verification Test.