Pinpoint Test B: The Instrument Cluster (Ic) Illumination Is Inoperative

WARNING: This page is about a different car, the 2008 Ford RV Cutaway, 2008 Ford Econoline, 2008 Ford E450 Super Duty, and 2008 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

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

B1 CHECK CIRCUIT 19 (LB/RD) FOR AN OPEN
- Key in OFF position.
- Disconnect: IC C220b
- Place the headlamp switch in the PARK position and rotate the headlamp switch knob fully counterclockwise without turning on the interior lamps.
- Measure the voltage between the IC C220b-26, circuit 19 (LB/RD), harness side and ground.
- Is the voltage greater than 10 volts?
1. YES : Go to B2.
2. NO : REPAIR the circuit. TEST the system for normal operation.
B2 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Disconnect: IC C220a
- Measure the resistance between the IC C220a-10, circuit 57 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
1. YES : Go to B3.
2. NO : REPAIR the circuit. TEST the system for normal operation.
B3 CHECK FOR CORRECT IC OPERATION
- Disconnect all the IC connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the IC connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new IC. REFER to INSTRUMENT CLUSTER (IC) AND WARNING CHIMES article. TEST the system for normal operation.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.