What it means
The engine coolant temperature 5 signal does not match plausibility checks against related signals. Sensor drift.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The Engine Coolant Temperature Sensor 5 reports coolant temperature to the engine control module, which compares its reading with other temperature signals and expected warm-up behavior. This code sets when Sensor 5's reading is implausible relative to those checks, consistent with a drifting sensor or one displaced from its reference path.
Common causes
Most likely first.
- Sensor characteristic drifted
- Sensor mounting displaced from reference path
- Sensor element aged beyond calibration window
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
How to diagnose it
- Review freeze-frame data and compare Sensor 5 with other coolant-temperature readings from a cold start to see when the readings begin to disagree.
- With the engine cold, inspect Sensor 5 and its mounting to confirm it is seated in the intended reference path and its connector is secure.
- Check Sensor 5 wiring and connector for damage, corrosion, loose pins, or signs of moisture that could distort the reading.
- Watch Sensor 5 live data through warm-up and look for an erratic reading or one that diverges from related temperature signals.
- Test the sensor response and circuit against the manufacturer's specification to distinguish sensor drift from a wiring fault.
Common fixes
- Reconnect or repair a loose or damaged Sensor 5 connector.
- Restore Sensor 5 to its correct mounting position.
- Repair damaged Sensor 5 wiring or connector terminals.
- Replace Engine Coolant Temperature Sensor 5 if its response is outside the manufacturer's specification.
Can I keep driving?
If the temperature gauge is normal and the engine is not overheating, a short, gentle drive may be possible, but monitor temperature closely. Avoid driving if temperature rises abnormally, the heater behavior changes sharply, or the engine runs poorly, since an inaccurate reading can interfere with cooling-fan and warm-up control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.