P0118
P0118-ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT HIGH
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
- Set Condition:
The Powertrain Control Module (PCM) detects that the Engine Coolant Temperature (ECT) Sensor input voltage is above the maximum acceptable value.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. PCM Pre-Diagnostic Troubleshooting Procedure.
Diagnostic Test
1. ACTIVE DTC
1. Start the engine and allow it to reach normal operating temperature.
WARNING:
When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
2. With the scan tool, select View DTCs.
Is the status Active for this DTC?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. PCM Intermittent Condition Test.
2. CHECK THE (K2) ECT SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Engine Coolant Temperature (ECT) Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (K2) ECT Signal circuit in the ECT Sensor harness connector.
Is the voltage above 5.2 volts?
Yes
- Repair the (K2) ECT Signal circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 3
3. CHECK THE (K2) ECT SIGNAL FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
3. Connect the (10436).
4. Measure the resistance of the (K2) ECT 1 Signal circuit between the ECT Sensor harness connector and the GPEC Adaptor.
Is the resistance below 5.0 Ohms?
Yes
- Go To 4
No
- Repair the (K2) ECT Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
4. CHECK THE (K900) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K900) Sensor Ground circuit between the ECT Sensor 1 harness connector and the GPEC Adaptor.
Is the resistance below 5.0 Ohms?
Yes
- Go To 5
No
- Repair the (K900) Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
5. ENGINE COOLANT TEMPERATURE SENSOR
1. Turn the ignition off.
2. Reconnect the PCM C2 harness connector.
3. Connect a jumper between the (K2) ECT Signal circuit and the (K900) Sensor Ground in the Engine Coolant Temperature Sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, read the ECT Sensor signal voltage.
Is the voltage below 0.1 volts with the jumper in place?
Yes
- Replace the Engine Coolant Temperature Sensor. Engine Coolant Temperature Sensor - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 6
6. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Coolant Temperature Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module (PCM). Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.