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

WARNING: This page is about a different car, the 2005 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

C1 CHECK CIRCUIT 1524 (DB) FOR VOLTAGE
- Key in OFF position.
- Disconnect: DSM C341c.
- Key in ON position.
- Measure the voltage between the DSM C341c pin 14, circuit 1524 (DB), harness side and ground.
  
  Fig 1: Measuring Voltage Between DSM C341c Pin 14, Circuit 1524 (DB), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to C2.
- No : REPAIR the circuit. REPEAT the self-test.
C2 CHECK CIRCUIT 490 (RD) FOR VOLTAGE
- Disconnect: DSM C341b.
- Measure the voltage between the DSM C341b pin 2, circuit 490 (RD), harness side and ground.
  
  Fig 2: Measuring Voltage Between DSM C341b Pin 2, Circuit 490 (RD), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to C3.
- No : REPAIR the circuit. REPEAT the self-test.
C3 CHECK CIRCUIT 676 (PK/OG) FOR AN OPEN
- Measure the resistance between the DSM C341c pin 1, circuit 676 (PK/OG), harness side and ground.
  
  Fig 3: Measuring Resistance Between DSM C341c Pin 1, Circuit 676 (PK/OG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to C4.
- No : REPAIR the circuit. REPEAT the self-test.
C4 CHECK CIRCUIT 57 (BK) FOR AN OPEN
- Measure the resistance between the DSM C341b pin 1, circuit 57 (BK), harness side and ground.
  
  Fig 4: Measuring Resistance Between DSM C341b Pin 1, Circuit 57 (BK), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : Refer to MODULE COMMUNICATIONS NETWORK to continue diagnosis of the communication network.
- No : REPAIR the circuit. REPEAT the self-test.