HVAC - Automatic

DTC B1023

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor
DTC B1023 05
- Integral Switch Performance Short to Ground

DTC B1023 06
- Integral Switch Performance Short to Battery or Open

DTC B1023 61
- Integral Switch Performance Signal Invalid

Circuit/System Description

This DTC is not associated with any wiring. It is an internal fault inside the HVAC control module for a stuck or shorted control button.

Conditions for Running the DTC

Battery voltage is between 9-16 volts and data link communications operate normally.

Conditions for Setting the DTC

The HVAC control module has internal fault inside the HVAC control module for a stuck or shorted control button.

Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Circuit/System Verification

1. Reprogram the HVAC control module that set DTC B1023. The module should successfully reprogram.

• If the module will not reprogram, replace the HVAC control module that set the DTC.

2. With a scan tool, clear the DTC.
3. Ignition OFF.
4. Wait 60 seconds, then recheck for DTCs. DTC B1023 should not set.

• If DTC B1023 sets, replace the module.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Programming and Relearningfor control module replacement, setup, and programming