Faulty coolant temperature sensor 3 (internal open circuit); Damaged, corroded or loose sensor connector with high resistance or poor contact; Open circuit in the signal or ground wire between the sensor and the control unit; Signal wire shorted to a voltage supply; Low coolant level leaving the sensor exposed to air, giving a false reading; Fault inside the engine control unit or a related control unit.

P01E6

Engine Coolant Temperature Sensor 3 Circuit High.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
1: AreaFuel and air metering
E6: FaultThe specific fault in that area

What it means

P01E6 is a generic code meaning the control unit has detected a high voltage signal on the circuit for engine coolant temperature sensor 3. A high voltage reading usually points to an open circuit, a short to voltage or a failed sensor, and it often equates to an implausibly low temperature. Which part of the cooling system sensor 3 monitors depends on the vehicle and engine, so check the manufacturer's information.

Symptoms

Engine warning light on
Temperature gauge reading low, erratic or not moving
Cooling fans running constantly or not at the right time
Hard starting or rough running, especially when warm
Poor fuel economy
Heater output poor or inconsistent

Possible causes

Faulty coolant temperature sensor 3 (internal open circuit)likely
Damaged, corroded or loose sensor connector with high resistance or poor contactlikely
Open circuit in the signal or ground wire between the sensor and the control unitlikely
Signal wire shorted to a voltage supplypossible
Low coolant level leaving the sensor exposed to air, giving a false readingpossible
Fault inside the engine control unit or a related control unitrare

How to diagnose

Read all stored and pending codes and record the freeze frame data, noting coolant temperature and engine load when the fault set.
Check the coolant level when the engine is cold and look for leaks or signs of air in the system.
Inspect the sensor, its connector and the nearby wiring for damage, corrosion, water ingress, chafing or heat damage.
Using live data, compare the sensor 3 reading with the other coolant temperature readings on a cold engine; they should be similar.
Unplug the sensor and check the live reading and the reference voltage at the connector against the manufacturer's specification.
Measure the sensor resistance at a known temperature and compare it with the specification for that model.
Check the signal and ground wires for continuity and for shorts to voltage or ground with the control unit disconnected, following the wiring diagram.
Clear the code and road test to confirm it does not return.

How to fix

Replace coolant temperature sensor 3 if its resistance is out of specification.
Clean, repair or replace a corroded or damaged connector and terminals.
Repair or replace any open or shorted wiring in the sensor circuit.
Top up or refill the coolant to the correct specification and bleed the air from the system.
Repair the cause of any coolant loss found during the checks.
Diagnose and, if confirmed faulty, replace or repair the control unit only after all wiring and sensor faults are ruled out.

Can I keep driving?

Medium severity

The car can usually be driven short distances, but the control unit may be using an incorrect temperature value, which can affect fuelling and fan control. Watch the temperature gauge, and stop if it overheats. Get it diagnosed soon.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.