What it means
The ECM detects a circuit intermittent/erratic fault on the engine coolant temperature sensor 6. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Engine coolant temperature sensor 6 supplies a temperature signal that the ECM uses for engine and cooling-system control. This code sets when that signal from sensor 6 changes erratically or drops out intermittently, often because the connector loses contact or the ground reference is unstable.
Common causes
Most likely first.
- Sensor connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
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 graph sensor 6 live temperature while the engine warms; look for abrupt jumps or dropouts that do not match actual warm-up.
- Inspect sensor 6 and its connector for an incompletely seated plug, corrosion, loose pins, or damaged wiring.
- With live data displayed, gently move the sensor 6 harness and connector to see whether the reading changes when the fault occurs.
- Inspect the sensor 6 ground-reference wiring and connections for looseness, corrosion, or damage.
- If the connector and wiring remain stable, test sensor 6 and its circuit under the manufacturer's procedure to isolate an intermittent sensor fault.
Common fixes
- Seat and secure the sensor 6 connector.
- Clean or repair loose or corroded connector terminals.
- Repair damaged sensor 6 wiring or ground-reference connections.
- Replace engine coolant temperature sensor 6 if its signal remains erratic with sound wiring.
Can I keep driving?
Use caution and avoid long trips if the temperature display, fan operation, or heater behavior changes unpredictably. An intermittent reading can cause incorrect cooling control and may hide an overheating condition.
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.