B3659

DTC B3659

DTC Descriptors

DTC B3659
- Head-Up Display (HUD) Dimming Down Switch Short to Ground.

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






Circuit/System Description

The head-up display (HUD) dimming down switch is a momentary press switch that adjusts the HUD display brightness. The HUD dimmer down switch controls the intensity of the brightness. The HUD senses when the dimming down switch is active and adjusts the display brightness until the desired intensity is attained. When the HUD illumination reaches the minimum intensity, the HUD will turn off the display by the next dimming down switch input. The HUD does not have a seperate Off switch. The HUD is turned off using the dimming down switch. When the HUD dimming down switch is pressed and the ignition is in the RUN position, the dimming down switch signal to the HUD is low. A press and hold of the dimming down switch greater than 500 msec initiates a smooth decrease in the HUD intensity until the switch is released or the HUD is turned off.

Conditions for Running the DTC

The ignition is in RUN.

Conditions for Setting the DTC

The HUD detects that the HUD dimming down switch signal circuit is low for greater than 60 seconds.

Action Taken When the DTC Sets

The HUD ignores the malfunctioning switch circuit.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The HUD receives a clear code command from the scan tool.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the head-up display (HUD).
2. Verify a test lamp does not illuminate when connected between the HUD dimming down switch signal circuit and B+.

• If the test light illuminates, test the HUD dimming down switch signal circuit for a short to ground. If the circuit tests normal, replace the HUD.

3. If all circuits test normal, test or replace the HUD switch.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Refer to Programming and Relearning.Programming and Relearning
* Head Up Display Switch Replacement