Pinpoint Test G: The Front Display Interface Module (FDIM) Illumination Does Not Operate Correctly

Information and Entertainment System

Pinpoint Tests

Pinpoint Test G: The Front Display Interface Module (FDIM) Illumination Does Not Operate Correctly

Normal Operation

The Front Display Interface Module (FDIM) receives the illumination signal from the Smart Junction Box (SJB) and dims the illumination based on the position of the dimmer switch. In the event this signal is lost, the FDIM defaults to full nighttime brightness, resulting in a symptom of the FDIM being unable to dim.

This pinpoint test is intended to diagnose the following:

- Backlighting system concern
- FDIM



PINPOINT TEST G: THE FDIM ILLUMINATION DOES NOT OPERATE CORRECTLY

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G1 CHECK FOR DTC U0140


- Carry out the FDIM self-test.
- Is DTC U0140 present?

Yes
GO to Pinpoint Test N. Pinpoint Test N: DTC U0140 Or DTC U0140:00

No
GO to G2.

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G2 CHECK THE ILLUMINATION SIGNAL


- Enter the following diagnostic mode on the scan tool: FDIM DataLogger.
- Monitor the FDIM illumination PID (ILL_FDIM) with the headlamp switch in the OFF position, and with the headlamp switch in the PARKING LAMPS position, while scrolling the dimmer switch from the lowest setting to the highest setting.
- Does the ILL_FDIM PID indicate "Max Daytime" with the headlamp switch off, and indicate an increasing number (1-18, Max Daytime) as the dimmer switch is scrolled?

Yes
GO to G3.

No
REFER to Instrument Panel, Gauges and Warning Indicators to diagnose the backlighting system.

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G3 CHECK FOR CORRECT FDIM OPERATION


- Disconnect the FDIM connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the FDIM connector and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?

Yes
INSTALL a new FDIM. REFER to Front Display Interface Module (FDIM) Front Display Interface Module (FDIM). TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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