The head-up display (HUD) is a secondary display system capable of reflecting important vehicle information onto the windshield. Vehicle information is displayed using virtual imaging and is reflected off the windshield in front of the driver. Battery positive voltage is the power source to the HUD system. The HUD system can only be enabled when the ignition is active and in RUN position. The HUD receives vehicle information to be displayed via serial data circuit. The HUD interfaces with the HUD switch via discreet circuits and the HUD switch inputs to the HUD is low.

Schematic Reference

Head Up Display Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Head Up Display (HUD) Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, verify that the HUD image is displayed on the windshield.

⇒	If the HUD image is not displayed, refer to HUD Inoperative.

2. Ignition ON, verify that when the HUD switches are pressed and released the HUD scan tool parameters toggle between Active and Inactive.

⇒	If the parameters do not toggle between Active and Inactive, refer to HUD Switch Malfunction.

HUD Inoperative

1. Ignition OFF, disconnect the harness connector at the HUD switch.
2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal 5 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the HUD.

3. Verify the scan tool Display Dimming parameter is greater than 98 percent.

⇒	If less than the specified range, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the HUD.

4. Install a 3A fused jumper wire between the HUD signal circuit terminal 4 and the low reference circuit terminal 5. Verify the scan tool Display Dimming parameter is less than 2 percent.

⇒	If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the HUD.

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

HUD Switch Malfunction

1. Ignition OFF, disconnect the harness connector at the head-up display (HUD)/Dimmer switch.
2. Test for less than 1.0 ohm between the low reference circuit terminal 5 and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance.

3. Ignition ON, verify that all of the scan tool HUD switch parameters are Inactive.

⇒	If not Inactive, test the signal circuit terminals listed below for a short to ground. If the circuit tests normal, replace the HUD.

•	Image Down Switch Signal Terminal 6

•	Image Up Switch Signal Terminal 7

4. Install a 3A fused jumper wire between the HUD switch signal circuit terminals listed below and the low reference circuit terminal 5. Verify the scan tool Adjust Display Down Switch or Adjust Display Up Switch parameter is Active.

•	Image Down Switch Signal Terminal 6

•	Image Up Switch Signal Terminal 7

⇒	If not Active, test the switch signal circuit for an open/high resistance. If the circuit(s) test normal, replace the HUD.

5. Verify the scan tool Display Dimming parameter is greater than 98 percent.

⇒	If less than the specified range, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the HUD.

6. Install a 3A fused jumper wire between the signal circuit terminal 4 and the low reference circuit terminal 5. Verify the scan tool Display Dimming parameter is less than 2 percent.

⇒	If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the HUD.

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

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.