How to deal with P0118 trouble code?
2 Answers
P0118 trouble code: refers to the high input of the engine coolant temperature circuit, indicating a fault with the coolant temperature sensor. The solutions for the P0118 trouble code are as follows: 1. Check if the coolant level is sufficient. If not, replenish the coolant. Additionally, replace the engine coolant regularly, typically every 2 years or 40,000 kilometers; 2. Inspect whether the thermostat, water pump, and cooling fan in the cooling system are functioning properly and if the coolant is circulating. This issue requires professional technician intervention; 3. Examine the coolant temperature sensor and its wiring for short circuits, open circuits, or poor contact. This problem should also be addressed by a professional technician.
When my previous car showed the P0118 trouble code, it was really worrying because it indicated a high signal from the coolant temperature sensor, making the engine computer think it was overheating. If left unresolved, the car would behave oddly: hard starts, skyrocketing fuel consumption, reduced performance, or even overheating and stalling. I recommend pulling over first to check the coolant level—top it up if it's low, as insufficient coolant can cause the sensor to falsely report high temperatures. Then, use a simple diagnostic tool to scan the trouble code to confirm P0118. If it's not a false alarm, tighten the sensor connector—located in the engine bay, as a loose connection might cause a high signal. If that doesn’t help, the sensor likely needs replacement. Buying the part and replacing it yourself isn’t too hard, but beginners are better off going to a repair shop—they have tools to test for circuit shorts and avoid wasting money. Don’t ignore the issue; safety is more important than anything. I learned the hard way by delaying repairs, turning a minor fix into a major one. Remember to regularly maintain and inspect the sensor and cooling system.
