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Code 51: Abnormal Valve Relay

DIAGNOSIS: 

TROUBLE SYMPTOM: 

WIRING DIAGRAM: 

Fig 1: Wiring Diagram
G02010902
  1. 8V1: CHECK INPUT VOLTAGE OF ABSCM & H/U. 
    1. Turn ignition switch to OFF.
    2. Disconnect connector from ABSCM & H/U.
    3. Run the engine at idle.
    4. Measure voltage between ABSCM & H/U connector and chassis ground.

    Connector & terminal 

    1. (F49) No. 1 (+) - Chassis ground (-): 
    2. (F49) No. 24 (+) - Chassis ground (-): 
    Fig 2: Measuring Voltage Between ABSCM & H/U Connector & Chassis Ground
    G02010903

    CHECK: Is the voltage between 10 and 15 V? 

    1. YES:  Go to step 8V2. 
    2. NO:  Repair harness connector between battery and ABSCM & H/U.
  2. 8V2: CHECK GROUND CIRCUIT OF ABSCM & H/U. 
    1. Turn ignition switch to OFF.
    2. Measure resistance between ABSCM & H/U connector and chassis ground.

    Connector & terminal 

    1. (F49) No. 23 - Chassis ground: 
    Fig 3: Measuring Resistance Between ABSCM & H/U Connector & Chassis Ground
    G02010904

    CHECK: Is the resistance less than 0.5 ohm? 

    1. YES:  Go to step 8V3. 
    2. NO:  Repair ABSCM & H/U ground harness.
  3. 8V3: CHECK VALVE RELAY IN ABSCM & H/U. 

    Measure resistance between ABSCM & H/U and terminals.

    Terminals 

    1. No 23 (+) - No. 24 (-): 
    Fig 4: Measuring Resistance Between ABSCM & H/U & Terminals
    G02010905

    CHECK: Is the resistance more than 1 Mohm? 

    1. YES:  Go to step 8V4. 
    2. NO:  Replace ABSCM & H/U, see ABS CONTROL MODULE AND HYDRAULIC CONTROL UNIT (ABSCM & H/U)  .
  4. 8V4: CHECK POOR CONTACT IN CONNECTORS. 

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

    1. YES:  Repair connector.
    2. NO:  Go to step 8V5. 
  5. 8V5: 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 8V6. 
  6. 8V6: 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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