Code 6, Coolant (TW) Sensor
- Turn off ignition. Remove "EFI/ECU" fuse in under-hood relay panel for 10 seconds to reset ECU. Start engine. Check if warning light is on. If not on, problem is intermittent. Test drive and check light again.
- If light is on, warm engine to normal operating temperature (cooling fan comes on). Disconnect 2-wire coolant sensor connector. Measure resistance across sensor terminals.
- If resistance is not 200-400 ohms, replace TW sensor. If resistance is within specification, measure voltage between ground and Yellow/Green wire of sensor harness. If reading is not about 5 volts, go to step 5). If reading is about 5 volts, measure voltage between Yellow/Green (pos.) and Green/White wires of connector harness.
- If voltage is not about 5 volts, repair open Green/White (neg.) wire between ECU terminal A16 and sensor. If voltage reading is correct, substitute a known good ECU. If condition is rectified, replace original ECU.
- If voltage reading between ground and Yellow/Green wire of sensor harness in step 3) was not about 5 volts, turn ignition off. Connect system checker harness between ECU and ECU connectors. Turn ignition on. Measure voltage between terminals A3 (pos.) and A16 (neg.) If voltage reading is about 5 volts, repair open Yellow/Green wire between ECU terminal A3 and TW sensor.
- If reading is not about 5 volts, disconnect "A" connector from main wire harness only, not the ECU. Measure voltage between terminals A3 (pos.) and A16 (neg.). If reading is not about 5 volts, go to step 7). If voltage reading is about 5 volts, repair short in Yellow/Green wire between ECU terminal A3 and sensor or repair short in Yellow/Green wire between TW sensor and automatic transmission control unit.
- If voltage reading is still not about 5 volts, substitute a known good ECU. If condition is rectified, replace original ECU.