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Home >> Honda >> 2002 >> Civic Si >> Repair and Diagnosis >> Engine Performance >> System >> Idle Control System (Hatchback) >> Electrical Power Steering (EPS) Signal Circuit Troubleshooting
July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Electrical Power Steering (EPS) Signal Circuit Troubleshooting

  1. Turn the ignition switch ON (II)
  2. Measure voltage between ECM connector terminals A24 and E16.
    1. Is there battery voltage? 
      1. YES:  Go to step  6.
      2. NO:  Go to step 3.
      2. Fig 1: Measuring Voltage Between ECM Connector Terminals A24 And E16
      G01399535Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Start the engine.
  4. Turn the steering wheel to the full lock position.
  5. Measure voltage between ECM connector terminals A24 and E16.
    1. Is there momentary battery voltage? 
      1. YES:  The EPS signal is OK.
      2. NO:  Go to step  10.
  6. Turn the ignition switch OFF.
  7. Disconnect the EPS control unit 20P connector.
  8. Turn the ignition switch ON (II).
  9. Measure voltage between EPS control unit terminal No. 17 and body ground.
    1. Is there battery voltage? 
      1. YES:  Substitute a known-good EPS control unit and recheck.
      2. NO:  Repair open in the wire between the ECM (E16) and the EPS control unit.
      2. Fig 2: Measuring Voltage Between EPS Control Unit Terminal No. 17 And Body Ground
      G01399536Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Turn the ignition switch OFF.
  11. Disconnect the EPS control unit 20P connector.
  12. Turn the ignition switch ON (II).
  13. Measure voltage between EPS control unit terminal No. 17 and the body ground.
    1. Is there battery voltage? 
      1. YES:  Substitute a known-good EPS control unit and recheck.
      2. NO:  Go to step 14.
      2. Fig 3: Measuring Voltage Between EPS Control Unit Terminal No. 17 And The Body Ground
      G01399537Courtesy of AMERICAN HONDA MOTOR CO., INC.
  14. Turn the ignition switch OFF.
  15. Disconnect the ECM connector E (31P).
  16. Check for continuity between body ground and ECM connector terminal E16.
    1. Is there continuity? 
      1. YES:  Repair short in the wire between the ECM (E 16) and the EPS control unit.
      2. NO:  Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck (see ECM UPDATING AND SUBSTITUTION FOR TESTING ). If the symptom/indication goes away with a known-good ECM, replace the original ECM.
      2. Fig 4: Checking For Continuity Between Body Ground And ECM Connector Terminal E16
      G01399538Courtesy of AMERICAN HONDA MOTOR CO., INC.
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