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Home >> Acura >> 1991 >> Integra GS, 2D Hatchback, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Code 6: Coolant (TW) Sensor
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Code 6: Coolant (TW) Sensor

NOTE: For wiring diagrams, see WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. For vacuum diagrams, see VACUUM DIAGRAMS article in the ENGINE PERFORMANCE Section.
  1. Turn ignition off. Remove HAZARD fuse at battery positive terminal for 10 seconds to reset ECU. Start engine, and observe CHECK ENGINE and LED lights. If lights are off, problem is intermittent. Check for poor and loose connections at TW sensor and connectors C216 and C318 at right shock tower. Test drive, and check again.
  2. If CHECK ENGINE light is on and LED indicates Code 6, start and run engine until cooling fan comes on. Turn engine off. Measure resistance between sensor Red/White and Green wire terminals. See Fig 1 . If resistance value is not 200-400 ohms, replace coolant sensor.
    Fig 1: Identifying Coolant Sensor Connector
    G90D15027Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. If resistance value is within specification, turn ignition on. Measure voltage between Red/White (positive) terminal on sensor harness and ground. If about 5 volts are present, go to step 6). If voltage is not about 5 volts on A/T models, disconnect 18-pin connector from A/T control unit.
  4. Recheck voltage at Red/White (positive) wire terminal. If voltage is about 5 volts, replace A/T control unit. On all models, if about 5 volts are not present, repair open or short in Red/White wire between ECU terminal C6, A/T control unit and TW sensor.
  5. If wire is okay, substitute a known good ECU, and recheck. If condition goes away or specified voltage is now available, replace ECU.
  6. If voltage is about 5 volts from step 3), measure voltage between Red/White (positive) and Green (negative) wire terminals.
  7. If about 5 volts are not present, repair open in Green wire between ECU connector C12 and TW sensor. If about 5 volts are present, substitute a known good ECU. If system operates properly, replace ECU.