DTC 22 - ECT Sensor Voltage Too High - TEST FC-7A

1. Using DRB-II, read Engine Coolant Temperature (ECT) sensor voltage. If voltage is greater than 4.5 volts, go to step 3). If voltage is 4.5 volts or less, wiggle ECT sensor connectors and harness while monitoring DRB-II. If voltage changed when harness and connectors were wiggled, repair harness or connector where wiggling caused voltage change. Perform TEST VER-1.
2. If voltage did not change when harness and connectors were wiggled, condition required to set fault is not present at this time. ECT SENSOR VOLTAGE TOO HIGH fault sets if coolant sensor circuit voltage at terminal No. 2 goes to more than 4.9 volts. Possible causes are sensor circuit open, sensor open internally and sensor ground wire open.
3. Inspect wiring and connectors. Repair harness or connector as necessary. Perform TEST VER-1. If no problems were found with wiring and connectors, see INACTIVE FAULT CONDITION. Test is complete. Perform TEST VER-1.
4. Disconnect ECT sensor connector. Connect jumper wire between ECT sensor connector, signal circuit (Tan/Black wire) and ground circuit (Black/Light Blue wire). Using DRB-II, read ECT sensor voltage. If reading is less than one volt, replace ECT. Perform TEST VER-1. If reading is one volt or more, move jumper wire from ECT sensor connector, ground circuit (Black/Light Blue wire) to engine ground.
5. Using DRB-II, read ECT sensor voltage. If reading is less than one volt, repair open sensor ground wire. Perform TEST VER-1. If reading is one volt or more, turn ignition off. Disconnect Powertrain Control Module (PCM).
6. Using an external ohmmeter, check resistance of ECT sensor connector, signal circuit (Tan/Black wire). If resistance is less than 5 ohms, replace PCM. Perform TEST VER-1. If resistance is 5 ohms or more, repair open ECT sensor signal wire. Perform TEST VER-1