B3744

DTC B3744

DTC Descriptors

DTC B3744
- Head-Up Display (HUD) Mode Switch Short to Ground

Diagnostic Fault Information

Important: Always 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) mode switch is a momentary contact switch. The HUD monitors the mode switch signal circuit in order to perform the mode switch functions. The HUD mode switch allows the driver to select a mode format to be displayed. Each press of the mode switch displays the next available mode and overriding the current mode displayed. The HUD has three modes available through the mode switch: Mode 1-Street Mode, Mode 2-Track Mode 2 and Mode 3-Track Mode 2. Vehicle information and warnings can also be acknowledged or removed by pressing the mode switch. When the HUD mode switch is pressed and the ignition is in the RUN position, the switch signal to the HUD is low.

Conditions for Running the DTC

The ignition is in RUN.

Conditions for Setting the DTC

The HUD detects that the HUD mode switch signal circuit is low for greater than 60 seconds.

Action Taken When the DTC Sets

The HUD ignores the malfunctioning switch circuit.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The HUD receives a clear code command from the scan tool.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the head-up display (HUD) switch.
2. Test for less than 1.0 ohm of resistance between the HUD switch ground circuit and ground.

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

3. Ignition ON, verify the scan tool mode switch parameter is Inactive.

• If not Inactive, test the mode switch signal circuit for a short to ground. If the circuit tests normal, replace the HUD.

4. Install a 3-A fused jumper wire between the mode switch signal circuit and ground. Verify the scan tool mode switch parameter is Active.

• If not Active, test the mode switch signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the HUD.

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

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Refer to Programming and Relearning.Programming and Relearning
* Head Up Display Switch Replacement