Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the HUD switch.
- Test for less than 5.0 ohm between the low reference circuit terminal 1 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance.
- Ignition ON, verify the scan tool Adjust Display Up Switch parameter is Inactive.
- If not Inactive, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the HUD.
- Install a 3A fused jumper wire between the switch signal circuit terminal 2 and the low reference circuit terminal 1. Verify the scan tool Adjust Display Up Switch parameter is Active.
- If not Active, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the HUD.
- If all circuits test normal, test or replace the HUD switch.