WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

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 CIRCUITS 601 (LB/PK) AND 493 (BK/PK) 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 601 (LB/PK), harness side and ground; and between the ABS module C155-32, circuit 493 (BK/PK), harness side and ground.
  
  Fig 1: Measuring Voltage Between ABS Module C155-4, Circuit 601 (LB/PK)
  Courtesy of FORD MOTOR CO.
- Are the voltages greater than 10 volts?
Yes

GO to A2.

No

REPAIR the circuit(s) in question. REPEAT the self-test.
A2 CHECK CIRCUIT 274 (BK/WH) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the ABS module C155-16, circuit 274 (BK/WH), harness side and ground.
  
  Fig 2: Measuring Resistance Between ABS Module C155-16, Circuit 274 (BK/WH)
  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. REPEAT the self-test.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Pinpoint Test A: No Communication With The Abs Module: Overview

Use the Manual With the Right Hardware

When to See a Mechanic

Rather have a pro handle this?