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Code 6 - Coolant Temperature (TW) Sensor

  1. Turn ignition off. Remove appropriate fuse for 10 seconds to reset ECU. See CLEARING CODES  . Start engine. Verify if CHECK ENGINE light is on and if LED is flashing Code 6. If Code 6 is present, go to next step. If Code 6 is not present, problem is intermittent. Check connectors at TW sensor and related circuits.
  2. Start engine, and warm to normal operating temperature (cooling fan comes on). Turn ignition off. Disconnect 2-wire coolant sensor connector. Measure resistance across sensor terminals.
  3. If resistance is not 200-400 ohms, replace TW sensor. If resistance is within specification, turn ignition on. Measure voltage between ground and Yellow/Green wire of TW sensor harness. If reading is about 5 volts, go to step 4). If reading is not about 5 volts, go to step 5) for A/T models or step 6) for M/T models.
  4. Measure voltage between Yellow/Green (+) and Green/White (-) wires. If reading is about 5 volts, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU. If voltage is not as specified, repair open in Green/White wire between ECU terminal D22 (C12 on 2.0L) and TW sensor.
  5. Disconnect 22-wire connector (18-wire connector on 2.0L) from A/T control unit. If voltage is now about 5 volts, replace A/T control unit. If reading is not about 5 volts, repair open or short in Yellow/Green wire between ECU terminal D13 (C6 on 2.0L), A/T control unit and TW sensor. If wire is okay, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU.
  6. Repair open or short in Yellow/Green wire between ECU terminal D13 (C6 on 2.0L) and TW sensor. If wire is okay, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU.
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