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INSPECTION PROCEDURE E-2: Keyless Entry System: The Front Dome Light, The Rear Dome Light < Vehicles Without Sunroof >, The Turn-Signal Lights And The Horn Do Not Operate Through The Answerback Function.: Diagnosis

Required Special Tools: 

  1. STEP 1. Verify the keyless entry system. 

    Q: Does the keyless entry system work normally? 

  2. STEP 2. Check the configuration function. 

    Q: Has the answerback function been enabled by means of the adjustment function? 

    • YES :  Go to Step 3.
    • NO :  Enable the answerback function by means of the adjustment function. Verify that the answerback functions work normally.
  3. STEP 3. Verify trouble symptom. 

    Q: Which answerback function is defective? 

    • Only the dome light :  Go to Step 4.
    • Only the turn-signal lights :  Go to  Step 5.
    • Only the horn :  Go to  Step 6.
    • None of the dome light and the turn-signal lights and the horn :  Replace the ETACS-ECU. Verify that the answerback functions work normally.
  4. STEP 4. Verify dome light operation. 

    Q: Does the dome light illuminate normally? 

  5. STEP 5. Verify turn-signal lights operation. 

    Q: Does the turn-signal lights work normally. 

  6. STEP 6. Verify which horn is defective. 

    Q: Which horn does not sound? 

    • Horn (HIGH) :  Go to Step 7.
    • Horn (LOW) :  Go to  Step 10.
    • Horn (HIGH or LOW) :  Go to  Step 13.
  7. STEP 7. Check horn (HIGH) connector A-18 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Is horn (HIGH) connector A-18 in good condition? 

    • YES :  Go to Step 8.
    • NO :  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the horn (HIGH) sounds normally.
    Fig 1: Identifying Horn (High) Connector A-18
    G02399695Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  8. STEP 8. Check the horn (HIGH). 

    Connect the battery as shown in illustration, and verify that the horn (HIGH) sounds.

    Q: Is the horn (HIGH) normal? 

    • YES :  Go to Step 9.
    • NO :  Replace the horn (HIGH). Verify that the horn (HIGH) sounds normally.
    Fig 2: Connecting Battery To Horn (High)
    G02399696Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  9. STEP 9. Check the wiring harness between horn relay connector A-05X (terminal 1) and horn (HIGH) connector A-18 (terminal 1). 
    Fig 3: Identifying Horn Relay Connector A-05X Terminals
    G02399697Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the wiring harness between horn relay connector A-10X (terminal 1) and horn (HIGH) connector A-18 (terminal 1) in good condition? 

    • YES :  No action is necessary and testing is complete.
    • NO :  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the horn (HIGH) sounds normally.
    Fig 4: Identifying Horn (High) Connector A-18
    G02399698Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  10. STEP 10. Check horn (LOW) connector A-19 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Is horn (LOW) connector A-19 in good condition? 

    • YES :  Go to Step 11.
    • NO :  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the horn (LOW) sounds normally.
    Fig 5: Identifying Horn (Low) Connector A-19
    G02399699Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  11. STEP 11. Check the horn. 

    Connect the battery as shown in illustration, and verify that the horn sounds.

    Q: Is the horn (LOW) normal? 

    • YES :  Go to Step 12.
    • NO :  Replace the horn (LOW). Verify that the horn (LOW) sounds normally.
    Fig 6: Connecting Battery To Horn
    G02399700Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  12. STEP 12. Check the wiring harness between horn relay connector A-05X (terminal 1) and horn (LOW) connector A-19 (terminal 1). 
    Fig 7: Identifying Horn Relay Connector A-05X
    G02399701Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the wiring harness between horn relay connector A-05X (terminal 1) and horn (LOW) connector A-19 (terminal 1) in good condition? 

    • YES :  No action is necessary and testing is complete.
    • NO :  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the horn (LOW) sounds normally.
    Fig 8: Identifying Horn (Low) Connector A-19
    G02399702Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  13. STEP 13. Check horn relay connector A-05X for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Are horn relay connector A-05X in good condition? 

    • YES :  Go to Step 14.
    • NO :  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the horn sounds normally.
    Fig 9: Identifying Horn Relay Connector A-05X
    G02399703Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  14. STEP 14. Check the horn relay. 
    Fig 10: Tester Connection & Specified Condition Chart
    G02399704Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is the horn relay normal? 

    • YES :  Go to Step 15.
    • NO :  Replace the horn relay. Verify that the horn sounds normally.
    Fig 11: Checking Horn Relay
    G02399705Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  15. STEP 15. Check the battery power supply circuit to the horn relay. Measured at horn relay connector A-05X. 
    1. Disconnect horn relay connector A-05X and measure the voltage available at the relay box side of the connector.
      Fig 12: Identifying Horn Relay Connector A-05X
      G02399706Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    2. Measure the voltage between terminal numbers 2, 4 and ground.
      • The voltage should equal approximately 12 volts (battery positive voltage).

    Q: Is the measured voltage approximately 12 volts (battery positive voltage)? 

    • YES :  Go to  Step 17.
    • NO :  Go to Step 16.
    Fig 13: Measuring Voltage Between Terminal Numbers 2, 4 And Ground
    G02399707Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  16. STEP 16. Check the wiring harness between horn relay connector A-05X (terminal 2 and 4) and the battery. 

    Q: Is the wiring harness between horn relay connector A-05X (terminal 2 and 4) and the battery in good condition? 

    • YES :  No action is necessary and testing is complete.
    • NO :  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the horn sounds normally.
    Fig 14: Identifying Horn Relay Connector A-05X
    G02399708Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  17. STEP 17. Check ETACS-ECU connector C-227 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 

    Q: Is ETACS-ECU connector C-227 in good condition? 

    • YES :  Go to Step 18.
    • NO :  Repair or replace the damaged component(s). Refer to HARNESS CONNECTOR INSPECTION . Verify that the horn sounds normally.
    Fig 15: Identifying ETACS-ECU Connector C-227 Terminals
    G02399709Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  18. STEP 18. Check the wiring harness between horn relay connector A-05X (terminal 3) and ETACS-ECU connector C-227 (terminal 44). 
    Fig 16: Identifying Horn Relay Connector A-05X
    G02399710Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 17: Identifying ETACS-ECU Connector C-227 Terminals
    G02399711Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    NOTE: Also check intermediate connector C-129 and joint connector C-21 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-129 or joint connector C-21 is damaged, repair or replace the damaged component(s) as described in HARNESS CONNECTOR INSPECTION .

    Q: Is the wiring harness between horn relay connector A-05X (terminal 3) and ETACS-ECU connector C-227 (terminal 44) in good condition? 

    • YES :  Go to Step 19.
    • NO :  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the horn sounds normally.
    Fig 18: Identifying Intermediate Connector C-129 And Joint Connector C-21 Terminals
    G02399712Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  19. STEP 19. Check the wiring harness between horn relay connector A-05X (terminal 1), horn (HIGH) connector A-18 (terminal 1) and horn (LOW) connector A-19 (terminal 1). 

    Q: Is the wiring harness between horn relay connector A-05X (terminal 1), horn (HIGH) connector A-18 (terminal 1) and horn (LOW) connector A-19 (terminal 1) in good condition? 

    • YES :  Replace the ETACS-ECU. Verify that the horn sounds normally.
    • NO :  The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Verify that the horn sounds normally.
    Fig 19: Identifying Horn Relay Connector A-05X
    G02399713Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    Fig 20: Identifying Horn (High) Connector A-18 And Horn (Low) Connector A-19
    G02399714Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.