P01E5: Engine Coolant Temperature Sensor 3 Circuit Low

Coolant temperature sensor 3 is a third NTC coolant sensor on engines with thermal management or split cooling circuits; its position is defined by the manufacturer – on Jaguar Land Rover's 2018–2019 Ingenium petrol engines it sits in the engine block water jacket, on Audi's 3.0 TFSI V6 it is part of the thermal management. As with every NTC sensor, a low signal voltage means hot and a high one cold. CARB requires such additional sensors to be monitored from model year 2019 onwards. P01E5 means the signal voltage is too low, so the module would read an implausibly hot coolant – typically a signal wire shorted to ground, coolant or moisture in the connector, or an internally shorted sensor. No manufacturer document using exactly this code was found; it is described by analogy with its documented sibling codes and the NTC principle.

Symptoms

• Check engine light on
• Coolant temperature or cooling fan behaviour possibly affected
• Often no change in driving

Most likely causes

• Signal wire of sensor 3 shorted to ground (chafing, water in connector)
• Sensor shorted internally
• Coolant in the connector, corrosion with leakage current
• Control module input stage faulty

What to check, in order

Start with the simplest. You can tick off each step.

1. With the engine cold, check the coolant level; never do this when the system is hot
2. With the connector unplugged, check whether the signal wire is making contact with ground.
3. Check the actual temperature in live data
4. Make sure the fan comes on when it should
5. Check the thermostat and connector
6. Measure the sensor and replace it if its readings do not make sense

Good to know

• Repair difficulty: easy
• It affects emissions.

What each character of P01E5 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 1: Air and fuel
• E5: Specific fault in that system

Frequently asked questions

Can I keep driving with code P01E5?

Watch the temperature gauge. If it climbs or a warning appears, stop the car in a safe place and turn off the engine: overheating can cause serious damage.

What causes code P01E5?

The most common causes are: signal wire of sensor 3 shorted to ground (chafing, water in connector); sensor shorted internally; coolant in the connector, corrosion with leakage current.

Related codes

• P01E3Engine Coolant Temperature Sensor 3 Circuit
• P01E4Engine Coolant Temperature Sensor 3 Circuit Range/Performance
• P01E6Engine Coolant Temperature Sensor 3 Circuit High
• P01E7Engine Coolant Temperature Sensor 3 Circuit Intermittent/Erratic
• P0117Engine Coolant Temperature Sensor 1 Circuit Low

Sources

• law.cornell.edu: 13 CCR 1968.2
• static.nhtsa.gov: MC 10162311 9999
• hella.com: test coolant temperature sensor

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.