Manual Three Zone Temperature Control

B210B-System Voltage High

For a complete wiring diagram, refer to.

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 DTC will set.

• When Monitored: Continuously with the ignition on.

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






Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to => Non-DTC Based Diagnostics. HVAC Pre-Diagnostic Troubleshooting Procedure

Test Step 1 - CHECK FOR CHARGING SYSTEM DTCS

• With the scan tool, read PCM DTCs.

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

Yes

• Perform the appropriate diagnostic procedure. Refer to => Electrical System DTC Based Diagnostics.

No

• Go to Test Step 2 => [ Test Step 2 - CHECK IF THE DTC IS ACTIVE ]

Test Step 2 - CHECK IF THE DTC IS ACTIVE

• With the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

• Go to Test Step 3 => [ Test Step 3 - CHECK IF OTHER CONTROLLER ARE REPORTING AN OVER VOLTAGE
CONDITION ]

No

• Go to Test Step 4 => [ Test Step 4 - CHECK THE WIRING AND CONNECTORS ]

Test Step 3 - CHECK IF OTHER CONTROLLER ARE REPORTING AN OVER VOLTAGE CONDITION

• Ignition on, engine not running.

• 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. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

Test Step 4 - CHECK THE WIRING AND CONNECTORS

• The conditions necessary to set the DTC are not present at this time.

• With the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.

• 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.

• 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. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

No

• Test complete.