HVAC - Automatic

DTC B1023

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* 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 after completing the diagnostic procedure. Verification Tests