Pinpoint Test B: No Communication With The Driver Seat Module (DSM)

WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

B1 CHECK CIRCUIT 566 (DG) FOR VOLTAGE
- Key in OFF position.
- Disconnect: DSM C341e.
- Key in ON position.
- Measure the voltage between the DSM C341e-1, circuit 566 (DG), harness side and ground.
  
  Fig 1: Measuring Voltage Between DSM C341e-1, Circuit 566 Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to B2.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
B2 CHECK CIRCUIT 1003 (GY/YE) FOR VOLTAGE
- Key in OFF position.
- Disconnect: DSM C341g.
- Key in ON position.
- Measure the voltage between the DSM C341g-1, circuit 1003 (GY/YE), harness side and ground.
  
  Fig 2: Measuring Voltage Between DSM C341g-1, Circuit 1003 Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to B3.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
B3 CHECK CIRCUIT 1203 (BK/LB) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the DSM C341g-6, circuit 1203 (BK/LB), harness side and ground.
  
  Fig 3: Measuring Resistance Between DSM C341g-6, Circuit 1203 Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to B4.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
B4 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
- Measure the resistance between the DSM C341e-2, circuit 1205 (BK), harness side and ground.
  
  Fig 4: Measuring Resistance Between DSM C341e-2, Circuit 1205 Harness Side And Ground
  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.