Head Up Display (HUD) Intensity Does Not Vary

Head Up Display (HUD) Intensity Does Not Vary

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 up or dimming down switch is a momentary press switch that adjusts the HUD display brightness. The HUD dimmer up or dimmer down switch controls the intensity of the brightness. The HUD senses when the dimming up or dimming down switch is active and adjusts the display brightness until the desired intensity is attained. When the HUD dimming up switch is pressed and the ignition is in the RUN position, the dimming up switch signal to the HUD is low. A press and hold of the dimming up switch greater than 500 msec initiates a smooth increase in the HUD intensity until the switch is released or maximum intensity is achieved. 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.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the head-up display (HUD).
2. Connect a test light between the HUD dimming up or dimming down switch signal circuit and B+. Verify a test light goes from full intensity to dim or dim to full intensity while adjusting the HUD dimmer up or dimmer down switch.

• If the test light does not go from full intensity to dim or dim to full intensity, test the HUD dimming up or dimming down switch signal circuit and the switch ground circuit for an open/high resistance. If the circuits test normal, replace the HUD switch.

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

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