B2474

DTC B2474

DIAGNOSTIC INSTRUCTIONS
- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
- Review Strategy Based Diagnosis for an overview of the diagnostic approach.
- Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC DESCRIPTOR

DTC B2474 07
Navigation Display Head Backlighting Performance

CIRCUIT DESCRIPTION
The internal backlighting of the navigation display screen located in the navigation radio.

CONDITIONS FOR RUNNING THE DTC
The radio must detect one of the following power modes:
- ACC
- ON
- RAP
- RAP UNLK

CONDITIONS FOR SETTING THE DTC
- The navigation radio test the navigation display backlighting antenna every 1 second.
- The radio determines there is a malfunction or overheat condition in the navigation display backlighting.

ACTION TAKEN WHEN THE DTC SETS
The navigation backlight may be too bright, dim or blank.

CONDITIONS FOR CLEARING THE DTC
- A current DTC goes to history when the radio does not detect the failure for more than 1 second.
- A history DTC clears after 50 ignition cycles with no repeat of the failure.

DIAGNOSTIC AIDS
Occasionally it's possible to overheat the navigation display backlighting due to excessive ambient heat inside the vehicle. In this instance it may be necessary to allow time for the display to cool.

CIRCUIT/SYSTEM TESTING
1. Allow the navigation display to cool if the ambient temperature inside the vehicle is excessive and the radio is hot to the touch. Verify the navigation display is cool and the DTC has cleared and gone to history.
- If the DTC has gone to history and the navigation display backlighting operates normal clear the DTC and go to diagnostic aids.
2. Observe the brightness of the navigation display backlighting. Verify the backlighting can be adjusted or the screen is not blank.
- If the display backlighting is malfunctioning or the DTC will not clear, replace the radio.

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

Control Module References for radio replacement, setup, and programming. Programming and Relearning