P CODES (POWERTRAIN) P0100 - P0199 P0116

If you own a vehicle and are experiencing issues with the engine coolant temperature circuit, you may see the P0116 code appear on your dashboard. This code indicates a range or performance problem in the engine coolant temperature circuit, and it's important to diagnose and address the issue promptly to avoid further damage to your vehicle. In this guide, we will explain the meaning of the P0116 code and provide a step-by-step guide to help you troubleshoot the problem.

What does the P0116 code mean?

The P0116 code is a diagnostic trouble code (DTC) that indicates a range or performance problem in the engine coolant temperature (ECT) circuit. This code is typically triggered when the engine control module (ECM) receives a signal from the ECT sensor that is outside of the normal range. The ECT sensor is responsible for measuring the temperature of the engine coolant and sending this information to the ECM, which uses it to adjust the fuel mixture and ignition timing. If the ECT sensor is malfunctioning, it can cause a variety of problems with the engine, including poor performance, decreased fuel efficiency, and even engine damage.

Step-by-Step Guide to Troubleshooting the P0116 Code

Step 1: Check for other codes
Before you start troubleshooting the P0116 code, it's a good idea to check for other codes that may be related to the engine coolant temperature circuit. If you see any additional codes, address those issues first before proceeding with the P0116 code.

Step 2: Inspect the ECT sensor
The first step in troubleshooting the P0116 code is to inspect the ECT sensor. The sensor is typically located on the engine block or in the thermostat housing, and it's connected to the engine wiring harness. Check the wiring and connections for any signs of damage, wear, or corrosion. If everything looks okay, test the resistance of the ECT sensor using a multimeter. Compare the readings with the manufacturer's specifications. If the readings are outside of the acceptable range, the sensor needs to be replaced.

Step 3: Check the thermostat
The thermostat is responsible for regulating the flow of coolant through the engine. If the thermostat is stuck open or closed, it can cause the engine to overheat or run too cool, which can trigger the P0116 code. To check the thermostat, start the engine and let it idle until it reaches normal operating temperature. Then, use a temperature gun or thermometer to measure the temperature of the upper radiator hose. If the temperature is significantly cooler than the engine temperature, the thermostat may be stuck open and needs to be replaced.

Step 4: Inspect the coolant system
The engine coolant system is a closed system that circulates coolant through the engine to regulate its temperature. If there is a leak in the system, it can cause the engine to overheat or run too cool, which can trigger the P0116 code. Inspect the coolant system for any signs of leaks, such as coolant stains or a drop in the coolant level. If you find a leak, repair it and refill the system with the recommended coolant.

Step 5: Check the ECM
If all of the previous steps have not resolved the issue, it's possible that the problem lies with the ECM itself. A malfunctioning ECM can cause a variety of problems with the engine, including issues with the engine coolant temperature circuit. To check the ECM, you will need to use a diagnostic tool that is compatible with your vehicle's make and model. If the tool indicates that the ECM is malfunctioning, it will need to be replaced.

Conclusion

The P0116 code is a serious issue that can cause a variety of problems with the engine, including decreased performance and decreased fuel efficiency. However, by following this step-by-step guide, you can troubleshoot and diagnose the issue with your engine coolant temperature circuit. Always remember to follow the manufacturer's recommendations when working on your vehicle. Addressing the P0116 code promptly will help you avoid further damage to your vehicle and keep it running smoothly for years to come.