Head Up Display (HUD) Inoperative

Head Up Display (HUD) Inoperative

Diagnostic Fault Information

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) 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. 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.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the HUD module.
2. Ignition OFF, test for less than 1.0 ohm of resistance between both HUD grounds and ground.

• If greater than 1.0 ohm, test the ground circuits for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the battery positive voltage circuit and ground.

• If the test lamp does not illuminate, repair the battery positive voltage circuit for a short to ground or an open/high resistance.

4. 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.

5. Ignition ON, dimmer switch at the off position, verify that a test lamp does not illuminate between the battery positive voltage circuit and the dimmer switch display signal circuit.

• If the test lamp does illuminate, test the dimmer switch display signal circuit for a short to ground. If the circuits test normal, replace the HUD switch.

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

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Head Up Display Switch Replacement (Rendezvous)
* Programming and Relearning for the HUD setup, and programming. Programming and Relearning