The head-up display (HUD) is a display system that optically projects vehicle information onto the windshield. The HUD has an electric tilt adjust that is controlled by the up and down switches. Operating these switches directs the motor to move the HUD image up or down on the windshield. There is also a page switch that can scroll through multiple messages present on the HUD. The HUD is also equipped with automatic dimming. Dimming is also controlled by a HUD dimmer switch. All three switches control the HUD by grounding the HUD switch input signals to ground. The dimmer switch uses a variable resistor to control HUD intensity where the lower the resistance, the brighter the HUD display.

Schematic Reference

Head Up Display Schematics

Connector End View Reference

Displays and Gages Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List

1. Ignition OFF, disconnect the harness connector at the HUD module.
2. Ignition ON, dimmer switch at the high intensity position, verify that a test lamp illuminates between the battery positive voltage circuit and the dimmer switch display signal circuit.

⇒	If the test lamp does not illuminate, test the dimmer switch display signal circuit and the dimmer switch ground circuit for an open/high resistance. If the circuits test normal, replace the HUD switch.

3. Ignition ON, connect a test lamp between the battery positive voltage circuit and the switch signal circuit. The test lamp should illuminate when either the up button, the down button, or the page button is pressed and should not illuminate when all of the buttons are not pressed.

⇒	If the test lamp does not illuminate when any of the buttons are pressed, test the up signal circuit for an open/high resistance. If the circuit tests normal, replace the HUD switch.

⇒	If the test lamp does illuminate when the buttons are not pressed, test the switch signal circuit for a short to ground. If the circuit tests normal, replace the HUD switch.

4. If all circuits test normal, test or replace the HUD module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.