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Pinpoint Test A: No Communication With The Vehicle Security Module

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

A1 CHECK THE VOLTAGE TO THE VEHICLE SECURITY MODULE
- Key in OFF position.
- Disconnect: Vehicle Security Module C2113b.
- Key in ON position.
- Measure the voltage between the vehicle security module C2113b-3, circuit 729 (RD/WH), harness side and ground; and between the vehicle security C2113b-1, circuit 1523 (DG), harness side and ground.
  
  Fig 1: Checking Voltage To Vehicle Security Module
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
Yes: GO to A2.

No: VERIFY the central junction box (CJB) fuse 5 (7.5A) and 20 (30A) are OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
A2 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Key in OFF position.
- Disconnect: Vehicle Security Module C2113a.
- Measure the resistance between the vehicle security module C2113a-14, circuit 57 (BK), harness side and ground.
  
  Fig 2: Checking Circuit 57 (BK) For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
Yes: REFER to MODULE COMMUNICATIONS NETWORK to continue communication diagnosis.

No: REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.