Pinpoint Test D: The Instrument Cluster Illumination Is Inoperative

WARNING: This page is about a different car, the 2004 Lincoln LS. 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.

D1 CHECK THE ILLUMINATION FEED CIRCUIT FOR VOLTAGE
- Disconnect: Instrument Cluster C220a.
- Key in ON position.
- Turn the headlamps on.
- Place the dimmer switch in the maximum brightness position.
- Measure the voltage between the instrument cluster C220a-7, circuit 64S-LK29 (BU/RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between Instrument Cluster C220A-7, Circuit 64S-LK29 (BU/RD), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
  1. Yes : GO to D2.
  2. No : REPAIR the circuit. TEST the system for normal operation.
D2 CHECK FOR CORRECT INSTRUMENT CLUSTER OPERATION
- Disconnect all the instrument cluster connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the instrument cluster connectors and make sure they seat correctly.
- Is the concern still present?
  1. Yes : INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER . TEST the system for normal operation.
  2. No : The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTC's. REPEAT the self-test.