P0116, P0117, P0118, P0119, P011B, P0125 | Engine Coolant Temperature (Sensor, Low/High, Including Thermostat Problems) |
If you own a Land Rover, you may encounter some trouble codes related to the engine coolant temperature sensor or the thermostat. These codes are P0116, P0117, P0118, P0119, P011B, and P0125. In this blog post, we will explain what these codes mean and how to diagnose and fix them.
The engine coolant temperature sensor (ECT) is a device that measures the temperature of the coolant in the engine. The ECT sends a signal to the engine control module (ECM), which uses it to adjust the fuel injection, ignition timing, and cooling fan operation. The ECT also helps the ECM to monitor the engine warm-up and cold-start emissions.
The thermostat is a valve that regulates the flow of coolant between the engine and the radiator. The thermostat opens and closes according to the coolant temperature, maintaining an optimal operating range for the engine. The thermostat also helps the engine to reach its normal operating temperature faster and reduce emissions.
The trouble codes P0116, P0117, P0118, P0119, P011B, and P0125 indicate that there is a problem with the ECT or the thermostat. Here is a brief description of each code:
- P0116: Engine Coolant Temperature Sensor 1 Circuit Range/Performance. This code means that the ECM detects an erratic or incorrect signal from the ECT.
- P0117: Engine Coolant Temperature Sensor 1 Circuit Low. This code means that the ECM detects a low voltage signal from the ECT, indicating that the coolant temperature is too low.
- P0118: Engine Coolant Temperature Sensor 1 Circuit High. This code means that the ECM detects a high voltage signal from the ECT, indicating that the coolant temperature is too high.
- P0119: Engine Coolant Temperature Sensor 1 Circuit Intermittent/Erratic. This code means that the ECM detects an intermittent or erratic signal from the ECT.
- P011B: Engine Coolant Temperature / Engine Oil Temperature Correlation. This code means that the ECM detects a discrepancy between the coolant temperature and the oil temperature signals.
- P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control. This code means that the ECM detects that the coolant temperature is too low for the engine to enter closed loop operation, which is a mode where the ECM adjusts the fuel mixture based on the oxygen sensor feedback.
To diagnose these codes, you will need a scan tool, a multimeter, and a thermometer. Here are some steps you can follow:
1. Connect the scan tool to the OBD port and retrieve the codes and freeze frame data. Note down any other codes that may be present and clear them all.
2. Check the coolant level and condition. If the coolant is low, dirty, or contaminated, top it up or flush it as needed.
3. Start the engine and let it idle until it reaches its normal operating temperature. Observe the scan tool data and compare it with the thermometer readings. The ECT should read within 10°F of the actual coolant temperature. If not, there may be a problem with the ECT or its wiring.
4. Turn off the engine and disconnect the ECT connector. Measure the resistance of the ECT with the multimeter and compare it with the specifications in your repair manual. The resistance should vary according to the temperature. If not, replace the ECT.
5. Check the wiring and connectors of the ECT for any signs of damage, corrosion, or loose connections. Repair or replace as needed.
6. Reconnect the ECT connector and start the engine again. Check if any of the codes reappear. If so, there may be a problem with the ECM or its wiring.
7. To test the thermostat, you can either use an infrared thermometer or remove it and place it in a pot of boiling water. The thermostat should open when it reaches its opening temperature (usually around 195°F). If not, replace it.
8. Check if any of the codes reappear after replacing or testing the thermostat.
If you follow these steps, you should be able to fix any of these trouble codes related to your Land Rover's engine coolant temperature sensor or thermostat. However, if you are not confident or experienced enough to perform these repairs yourself, we recommend that you take your vehicle to a professional mechanic for further diagnosis and service.
