Pinpoint Test A: No Communication With The Instrument Cluster

A1 CHECK THE INSTRUMENT CLUSTER POWER SUPPLY

Key in OFF position.
Disconnect: Instrument Cluster C220a and C220b.
Key in ON position.

Measure the voltage between the instrument cluster, harness side and ground, as follows:

INSTRUMENT CLUSTER CONNECTOR-PIN AND CIRCUIT REFERENCE CHART

Instrument Cluster Connector-Pin	Circuit
C220b-18	295 (LB/PK)
C220a-1	3049 (BK/LG)
C220a-7	489 (PK/BK)

Are the voltages greater than 10 volts?

Yes : GO to A2.
No : REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test.

A2 CHECK INSTRUMENT CLUSTER GROUND CIRCUITS 1205 (BK) AND 1203 (BK/LB)
- Key in OFF position.
- Measure the resistance between the instrument cluster C220b-11, circuit 1205 (BK), harness side and ground; and between the instrument cluster C220a-2, circuit 1203 (BK/LB), harness side and ground.
  
  Fig 1: Checking Instrument Cluster Ground Circuits 1205 (BK) And 1203 (BK/LB)
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
- Yes : REFER to MODULE COMMUNICATIONS NETWORK to continue communication diagnosis.
- No : REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test.