2001 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Code 41: Abnormal Abs Control Module

DIAGNOSIS: 

  • Faulty ABSCM & H/U.

TROUBLE SYMPTOM: 

  • ABS does not operate.

WIRING DIAGRAM: 

Fig 1: Wiring Diagram
G02010888
  1. 8S1: CHECK GROUND CIRCUIT OF ABSCM & H/U. 
    1. Turn ignition switch to OFF.
    2. Disconnect connector from ABSCM & H/U.
    3. Measure resistance between ABSCM & H/U and chassis ground.

    Connector & terminal 

    1. (F49) No. 23 - Chassis ground: 
    Fig 2: Measuring Resistance Between ABSCM & H/U & Chassis Ground
    G02010889

    CHECK: Is the resistance less than 0.5 ohm? 

    1. YES:  Go to step 8S2. 
    2. NO:  Repair ABSCM & H/U ground harness.
  2. 8S2: CHECK POOR CONTACT IN CONNECTORS. 

    CHECK: Is there poor contact in connectors between battery, ignition switch and ABSCM & H/U? 

    1. YES:  Repair connector.
    2. NO:  Go to step 8S3. 
  3. 8S3: CHECK SOURCES OF SIGNAL NOISE. 

    CHECK: Is the car telephone or the wireless transmitter properly installed? 

    1. YES:  Go to step 8S4. 
    2. NO:  Properly install the car telephone or the wireless transmitter.
  4. 8S4: CHECK SOURCES OF SIGNAL NOISE. 

    CHECK: Are noise sources (such as an antenna) installed near the sensor harness? 

    1. YES:  Install the noise sources apart from the sensor harness.
    2. NO:  Go to step 8S5. 
  5. 8S5: CHECK ABSCM & H/U. 
    1. Connect all connectors.
    2. Erase the memory.
    3. Perform inspection mode.
    4. Read out the trouble code.

    CHECK: Is the same trouble code as in the current diagnosis still being output? 

    1. YES:  Replace ABSCM & H/U, see ABS CONTROL MODULE AND HYDRAULIC CONTROL UNIT (ABSCM & H/U)  .
    2. NO:  Go to step 8S6. 
  6. 8S6: CHECK ANY OTHER TROUBLE CODES APPEARANCE. 

    CHECK: Are other trouble codes being output? 

    1. YES:  Proceed with the diagnosis corresponding to the trouble code.
    2. NO:  A temporary poor contact.
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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.