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Wiring Diagram:

Fig 1: Front Wheel Drive Switch Circuit
G02003639
  1. 9P1: CHECK FWD SWITCH. 

    CHECK: When fuse is inserted to FWD switch, does LED light up? 

    1. YES:  Go to step brake switch, see CHECK BRAKE SWITCH  .
    2. NO:  Go to step 9P2. 
  2. 9P2: CHECK HARNESS CONNECTOR BETWEEN TCM AND FWD SWITCH. 
    1. Turn ignition switch to OFF.
    2. Disconnect connector from FWD switch.
    3. Measure resistance of harness between TCM and FWD switch connector.

    Connector & Terminal 

    (B55) No. 14 - (F67) No. 30: 

    Fig 2: Measuring Resistance Of Harness Between TCM & FWD Switch Connector
    G02003640

    CHECK: Is the resistance less than 1 ohm? 

    1. YES:  Go to step 9P3. 
    2. NO:  Repair open circuit in harness between TCM and FWD switch connector.
  3. 9P3: CHECK HARNESS CONNECTOR BETWEEN TCM AND FWD SWITCH. 

    Measure resistance of harness connector between TCM and body to make sure that circuit does not short.

    Connector & Terminal 

    (B55) No. 14 - Chassis ground: 

    Fig 3: Measuring Resistance Of Harness Connector Between TCM & Body
    G02003641

    CHECK: Is the resistance more than 1 Mohm? 

    1. YES:  Go to step 9P4. 
    2. NO:  Repair short circuit in harness connector between TCM and chassis ground.
  4. 9P4: CHECK INPUT SIGNAL FOR TCM. 
    1. Turn ignition switch to OFF.
    2. Connect connector to FWD switch.
    3. Turn ignition switch to ON.
    4. Measure signal voltage for TCM while installing the fuse to FWD switch connector.

    Connector & Terminal 

    (B55) No. 14 (+) - Chassis ground (-): 

    Fig 4: Measuring Signal Voltage For TCM While Installing The Fuse To FWD Switch Connector
    G02003642

    CHECK: Is the voltage less than 1 V in FWD switch while installing? 

    1. YES:  Go to step 9P5. 
    2. NO:  Go to step  9P11.
  5. 9P5: CHECK INPUT SIGNAL FOR TCM. 

    Measure signal voltage for TCM while removing the fuse from FWD switch connector.

    Connector & Terminal 

    (B55) No. 14 (+) - Chassis ground (-): 

    Fig 5: Measuring Signal Voltage For TCM While Removing The Fuse From FWD Switch Connector
    G02003643

    CHECK: Is the voltage between 6 and 9.1 V in FWD switch while removing? 

    1. YES:  Go to step 9P6. 
    2. NO:  Replace TCM, see TRANSMISSION CONTROL MODULE (TCM) .
  6. 9P6: CHECK FWD INDICATOR LIGHT. 
    1. Turn ignition switch to OFF.
    2. Remove combination meter.
    3. Remove FWD indicator light bulb from combination meter.

    CHECK: Is FWD indicator light bulb OK? 

    1. YES:  Go to step 9P7. 
    2. NO:  Replace FWD indicator light bulb.
  7. 9P7: CHECK HARNESS CONNECTOR BETWEEN TCM AND COMBINATION METER. 
    1. Turn ignition switch to OFF.
    2. Disconnect connector from combination meter.
    3. Measure resistance of harness between TCM and combination meter connector.

    Connector & Terminal 

    (B54) No. 12 - (i12) No. 6: 

    Fig 6: Measuring Resistance Of Harness Between TCM & Combination Meter Connector
    G02003644

    CHECK: Is the resistance less than 1 ohm? 

    1. YES:  Go to step 9P8. 
    2. NO:  Repair open circuit in harness between TCM and combination meter and poor contact in coupling connector.
  8. 9P8: CHECK HARNESS CONNECTOR BETWEEN TCM AND COMBINATION METER. 

    Measure resistance of harness connector between TCM and chassis ground to make sure that circuit does not short.

    Connector & Terminal 

    (B54) No. 12 - Chassis ground: 

    Fig 7: Measuring Resistance Of Harness Connector Between TCM & Chassis Ground
    G02003645

    CHECK: Is the resistance more than 1 Mohm? 

    1. YES:  Go to step 9P9. 
    2. NO:  Repair short circuit in harness between TCM and combination meter connector.
  9. 9P9: CHECK OUTPUT SIGNAL EMITTED FROM TCM. 
    1. Turn ignition switch to OFF.
    2. Connect connector to combination meter.
    3. Turn ignition switch to ON.
    4. Measure signal voltage for TCM while installing and removing the fuse to FWD switch connector.

    Connector & Terminal 

    (B54) No. 12 - Chassis ground: 

    Fig 8: Measuring Signal Voltage For TCM While Installing & Removing The Fuse To FWD Switch Connector
    G02003646

    CHECK: Is the voltage less than 1 V in FWD switch while installing? 

    1. YES:  Go to step 9P10. 
    2. NO:  Go to step  9P11.
  10. 9P10: CHECK OUTPUT SIGNAL EMITTED FROM TCM. 

    Measure signal voltage for TCM while removing the fuse from FWD switch connector.

    Connector & Terminal 

    (B54) No. 12 - Chassis ground: 

    Fig 9: Measuring Signal Voltage For TCM While Removing The Fuse From FWD Switch Connector
    G02003647

    CHECK: Is the voltage more than 9 V in FWD switch while removing? 

    1. YES:  Go to step 9P11. 
    2. NO:  Replace TCM, see TRANSMISSION CONTROL MODULE (TCM) .
  11. 9P11: CHECK POOR CONTACT. 

    CHECK: Is there poor contact in FWD switch circuit? 

    1. YES:  Repair poor contact.
    2. NO:  Replace TCM, see TRANSMISSION CONTROL MODULE (TCM) .
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