HVAC

B210B-SYSTEM VOLTAGE HIGH





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

Theory of Operation

The A/C Heater Control constantly monitors battery and ignition voltage to ensure proper operation. If the voltage to the controller is out of range it could cause damage to the controller or its respective components. If the voltage of either circuit drops below or rises above a predetermined calibration a Diagnostic Trouble Code (DTC) will set.

- When Monitored:
With the ignition on.

- Set Condition:
If the controller battery voltage is higher than 16.0 volts for period of 5.0 seconds.





Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. HVAC Pre-Diagnostic Troubleshooting Procedure.

1. CHECK FOR CHARGING SYSTEM DTCS
1. Using the scan tool, read PCM DTCs.

Are there any charging system DTCs present in the Powertrain Control Module (PCM)?

Yes

- Testing and Inspection Perform the appropriate diagnostic procedure.

No

- Go To 2

2. CHECK FOR TOTALLY INTEGRATED POWER MODULE DTCS
1. Using the scan tool, read TIPM DTCs.

Are there any TIPM DTCs present?

Yes

- Testing and Inspection Perform the appropriate diagnostic procedure.

No

- Go To 3

3. CHECK IF THE DTC IS ACTIVE
1. Using the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

- Go To 4

No

- Go To 5

4. CHECK IF OTHER CONTROLLER ARE REPORTING AN OVER VOLTAGE CONDITION
1. Ignition on, engine not running.
2. With the scan tool read DTCs.

Are any other controllers reporting an over voltage condition?

Yes

- Go to DTC Based Diagnostics and perform the appropriate diagnostic procedure.

No

- Replace and program the A/C Heater Control.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

5. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. Using the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.
3. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. Wiggle the wiring and connectors while checking for shorted and open circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.