Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|
HUD Battery Positive Voltage Circuit | -- | 1 | -- |
HUD Dimming Up Switch Signal Circuit | B3634 | 1 | -- |
HUD Dimming Down Switch Signal Circuit | B3659 | 2 | -- |
HUD Ground Circuit | -- | 1 | -- |
HUD Switch Ground Circuit | -- | 1 2 | -- |
1. HUD Inoperative 2. HUD Always On | |||
Circuit/System Description
The head-up display (HUD) is a secondary display system capable of reflecting important vehicle information onto the windshield. The vehicle information is displayed using virtual imaging and is reflected on 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 the serial data circuit. The HUD system also receives vehicle and engine speed information via discreet vehicle and engine speed signal circuits. The HUD also interfaces with the HUD switch via discreet circuits and the HUD switch inputs to the HUD is low. A press and hold of the dimming up switch greater than 1 sec initiates a smooth increase in the HUD display intensity until the switch is released or maximum intensity is achieved. The HUD does not have a separate Off switch. The HUD is turned OFF using the dimming down switch. A press and hold of the dimming down switch greater than 1 sec initiates a smooth decrease in the HUD intensity until the switch is released or the HUD is turned OFF.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the HUD.
- Test for less than 1.0 ohm of resistance between the HUD ground circuit terminal 6 and ground.
- Verify a test lamp illuminates when connected between the HUD battery positive voltage circuit terminal 1 and the ground circuit terminal 6.
- Verify a test lamp illuminates when connected between the HUD dimming up switch signal circuit terminal 11 and B+ while pressing the HUD dimming up switch.
- Verify a test lamp illuminates when connected between the HUD dimming down switch signal circuit terminal 12 and B+ while pressing the HUD dimming down switch.
- If all circuits test normal, test or replace the HUD switch.
| ⇒ | If greater than 1.0 ohm, test the HUD ground circuit terminal 6 for an open/high resistance. |
| ⇒ | If the test light does not illuminate, test the HUD battery positive voltage circuit for an open/high resistance. |
| ⇒ | If the test light does not illuminate, test the HUD dimming up switch signal circuit for a short to voltage or an open/high resistance. If the circuit test normal, replace the HUD. |
| ⇒ | If the test light does not illuminate, test the HUD dimming down switch signal circuit for a short to voltage or an open/high resistance. If the circuit test normal, replace the HUD. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for the HUD replacement, setup and programming |
