Pinpoint Test E: The Instrument Panel Illumination Does Not Dim

WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.

E1 CHECK THE RECORDED INSTRUMENT CLUSTER DIAGNOSTIC TROUBLE CODES (DTCs)
- Check the recorded results from the instrument cluster self-test.
- Are any DTCs present?
Yes : If DTC B1246 is present, GO to E2.

For all other DTCs, REFER to the INSTRUMENT CLUSTER DIAGNOSTIC TROUBLE CODE (DTC) INDEX .

No : GO to E4.
E2 VERIFY DTC B1246
- Key in OFF position.
- Disconnect: Instrument Cluster C220.
- Measure the resistance between the instrument cluster C220-23, circuit 1011 (TN/OG), harness side and ground.
  
  Fig 1: Verify DTC B1246
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : GO to E7.

No : GO to E3.
E3 CHECK CIRCUIT 1011 (TN/OG) FOR A SHORT TO GROUND
- Disconnect: Instrument Panel Dimmer Switch C2065.
- Measure the resistance between the instrument cluster C220-23, circuit 1011 (TN/OG), harness side and ground.
  
  Fig 2: Checking Circuit 1011 (TN/OG) For Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : INSTALL a new instrument panel dimmer switch. CLEAR the DTC. REPEAT the self-test.

No : REPAIR the circuit. CLEAR the DTC. REPEAT the self-test.
E4 CHECK CIRCUIT 570 (BK/WH) FOR AN OPEN
- Key in OFF position.
- Disconnect: Instrument Panel Dimmer Switch C2065.
- Measure the resistance between the instrument panel dimmer switch C2065-5, circuit 570 (BK/WH), harness side and ground.
  
  Fig 3: Checking Circuit 570 (BK/WH) For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes : GO to E5.

No : REPAIR the circuit. TEST the system for normal operation.
E5 CHECK THE INSTRUMENT PANEL DIMMER SWITCH
- Carry out the instrument panel dimmer switch component test.
  Refer to COMPONENT TESTING -- ESCAPE & MARINER or COMPONENT TESTING -- ESCAPE HYBRID & MARINER HYBRID .
- Is the instrument panel dimmer switch OK?
Yes : GO to E6.

No : INSTALL a new instrument panel dimmer switch. TEST system for normal operation.
E6 CHECK CIRCUIT 1011 (TN/OG) FOR AN OPEN
- Disconnect: Instrument Cluster C220.
- Measure the resistance between the instrument cluster C220-23, circuit 1011 (TN/OG), harness side and the instrument panel dimmer switch C2065-3, circuit 1011 (TN/OG), harness side.
  
  Fig 4: Checking Circuit 1011 (TN/OG) For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes : GO to E7.

No : REPAIR the circuit. TEST the system for normal operation.
E7 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
- Disconnect the instrument cluster connector.
- Check for:
  - corrosion
  - pushed-out pins
- Connect the instrument cluster connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes : INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER . REPEAT the self-test.

No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.