After a long standstill, typically six to eight hours, the coolant should have cooled to roughly the outside air temperature measured by the ambient sensor in the bumper or mirror. P011E compares coolant temperature sensor 1 with the ambient sensor at start-up and is set when they differ beyond a calibrated limit and no preheater was detected. The code does not say which of the two sensors is wrong. No manufacturer document using exactly this code was found; the description rests on the CARB requirement for coolant sensor plausibility and on the same cold-soak comparison that Ford (reported as P0071), GM/Saab and Mazda perform under other codes.
Low severity. Can I keep driving?Yes, you can normally keep driving and take it to a repair shop when convenient.
Symptoms
- Check engine light on
- Usually no driving symptoms
- Outside temperature display possibly wrong
Most likely causes
- Coolant temperature sensor 1 drifting
- Ambient temperature sensor drifting or affected by engine heat or sun
- Preheater not detected
- Contact resistance in one sensor's connector or wiring
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It affects emissions.
What each character of P011E means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 1: Air and fuel
- 1E: Specific fault in that system
Frequently asked questions
Can I keep driving with code P011E?
Yes, you can normally keep driving and take it to a repair shop when convenient.
What causes code P011E?
The most common causes are: coolant temperature sensor 1 drifting; ambient temperature sensor drifting or affected by engine heat or sun; preheater not detected.
Related codes
- P011FEngine Coolant Temperature 2 / Ambient Air Temperature Correlation
- P011BEngine Coolant Temperature/Intake Air Temperature Correlation
- P011AEngine Coolant Temperature Sensor 1/2 Correlation
- P0116Engine Coolant Temperature Sensor 1 Circuit Range/Performance
- P0071Ambient Air Temperature Sensor Circuit A Range/Performance
Sources
- law.cornell.edu: 13 CCR 1968.2
- static.nhtsa.gov: MC 10168072 0001
- fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
- saabwisonline.com: dtc p0128
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.