Pinpoint Test A: No Communication With The Vehicle Security Module

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 pin 3, circuit 729 (RD/WH), harness side and ground; and between the vehicle security module C2113b pin 1, circuit 1523 (DG), harness side and ground.
  
  Fig 1: Measuring Voltage Between Vehicle Security Module C2113B Pin 3 Circuit 729 (RD/WH)
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
- Yes : GO to A2.
- No : 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 pin 14, circuit 57 (BK), harness side and ground.
  
  Fig 2: Measuring Resistance Between Vehicle Security Module C2113A Pin 14 Circuit 57 (BK)
  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.