Circuit Description
The backlighting error detection is determined inside the navigation display head (NDH). No external circuits are involved.
Conditions for Running the DTC
The navigation display head (NDH) checks for a backlighting internal error every five seconds during the following power modes:
| • | ACC |
| • | ON |
| • | RAP |
DTC B2474 does not set if DTC B1328 or DTC B1327 is current.
Conditions for Setting the DTC
A B2474 sets if any of the following conditions are present:
| • | Backlighting circuit/bulb failure. |
| • | Backlighting circuit current consumption is to high. |
| • | Backlighting heater is not providing heat. |
| • | The navigation display head (NDH) temperature is over 105°C (221°F). |
Action Taken When the DTC Sets
Any of the following may be observed:
| • | Black screen and the audio and navigation functions cannot be controlled. |
| • | The screen brightness is incorrect. |
| • | Changes to the screen brightness are inconsistent. |
Conditions for Clearing the DTC
The navigation display head (NDH) determines that the backlighting fault is not present.
Diagnostic Aids
This DTC may be stored as a history DTC without affecting the operation of the module. If stored only as a history DTC and not a current DTC, do not replace the module.
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
Determines if the malfunction is present.
-
Verifies that the DTC sets under normal operating conditions.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Did you perform Diagnostic System Check - Navigation System ? | -- | Go to Step 2 | ||
Is B2474 a current DTC? | -- | Go to Step 3 | ||
3 | Replace the navigation display head (NDH). Refer to Navigation Data Processor Replacement . Did you complete the replacement? | -- | Go to Step 4 | -- |
4 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
