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Pinpoint Test A: No Communication With The Anti-Lock Brake System (Abs) Module

CAUTION: Use the flex probe kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.

A1 CHECK CIRCUIT 677 (LB) AND CIRCUIT 483 (RD) FOR AN OPEN
- Key in OFF position.
- Disconnect: ABS Module C155.
- Key in ON position.
- Measure the voltage between the ABS module C155-4, circuit 677 (LB), harness side and ground; and between the ABS module C155-32, circuit 483 (RD), harness side and ground.
  
  Fig 1: Measuring Voltage Between ABS Module C155-4
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
- Yes : GO to A2.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
A2 CHECK CIRCUIT 570 (BK/WH) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the ABS module C155-16, circuit 570 (BK/WH) harness side and ground.
  
  Fig 2: Measuring Resistance Between ABS Module C155-16, Circuit 570 (BK/WH) Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : CHECK the module communications network. REFER to MODULE COMMUNICATIONS NETWORK .
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.