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Home >> Honda >> 1991 >> Civic Base, 2D Hatchback >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Diagnostic Codes >> Code 19 - Lock-Up Control Solenoid >> Civic A/T
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Civic A/T

  1. Turn ignition off. Remove ECU fuse for 10 seconds to reset ECU. Drive vehicle and observe CHECK ENGINE light. Verify if CHECK ENGINE light is on and if LED is flashing Code 19. If LED is flashing Code 19, go to next step. If LED is not flashing Code 19, problem is intermittent. Check connectors at lock-up solenoid and related circuits.
  2. Turn ignition off. Connect ECU Test Harness between ECU and ECU connector. See Figure . Disconnect connector "A" from ECU side only. Disconnect 2-wire connector from lock-up control solenoid valve.
  3. Check continuity between ECU terminal A8 and ground. See Figure . If continuity is present, repair short in Yellow wire between ECU terminal A8 and lock-up control solenoid valve 2-wire connector.
  4. If continuity does not exist, reconnect solenoid connector. Measure resistance between terminals A8 and A18. If resistance is 14-25 ohms, substitute a known good ECU. If condition is corrected, replace original ECU.
  5. If resistance is not as specified, check for continuity in Yellow wire between ECU terminal A8 and solenoid 2-wire connector. If continuity does not exist, repair open in Yellow wire. If continuity exists, replace faulty lock-up solenoid valve.
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