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 V 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

* The DTC will become history if the HVAC module no longer detects a failure.

* The history DTC will clear after 40 consecutive fault free ignition cycles have occurred.

Circuit/System Verification

1. Ignition ON

2. Verify DTC B1023 is not set.

• If DTC B1023 is set

1. Program the K33 HVAC control module.

2. Verify the DTC does not set.

• If the DTC sets, replace the K33 HVAC control module.

• If the DTC does not set

3. All OK

• If DTC B1023 is not set

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Control Module References Control Module References for control module replacement, programming, and setup