P01EE code meaning
Engine Coolant Heater B Control Circuit High
Powertrain system Generic code P01xx codes Check engine light
What P01EE means
Engine coolant heater B is an electric coolant heater switched by the engine module, directly or via a relay or power stage, to shorten warm-up – less cold-start emissions and faster cabin heat; A and B denote two separately switched heaters or stages. It is not the same as a mains-powered block heater (which the vehicle does not control) or the electrically heated thermostat (P0597–P0599). CARB requires output components to be checked for correct response or at least for circuit faults. This code reports a control circuit voltage that is too high – typically a short to battery voltage or overcurrent. No manufacturer using these codes was found in the GM, Ford or NHTSA documents checked; the typical driver diagnosis (open circuit detected with the driver switched off, as GM does for other outputs) is an analogy, and thresholds are unknown.
P01EE at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P01EE
- Check engine light on
- Longer warm-up, cabin heat slower in winter
- Usually no change in driving
Common causes of P01EE
- Most likelyControl wire shorted to battery voltage
- PossibleRelay coil or heater with too low resistance (overcurrent)
- PossibleHarness damage touching a positive wire
- Less likelyControl module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Engine coolant heater bHeater relayControl circuit wiring
What each part of P01EE means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 1 | Area: fuel and air metering. |
| EE | The exact fault in that area. |
What to do next
- Note P01EE and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P01EE
What does P01EE mean?
P01EE means "Engine Coolant Heater B Control Circuit High". Engine coolant heater B is an electric coolant heater switched by the engine module, directly or via a relay or power stage, to shorten warm-up – less cold-start emissions and faster cabin heat; A and B denote two separately switched heaters or stages. It is a generic code, so it means the same on every make.
Is it safe to drive with P01EE?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P01EE fail an emissions test?
Yes, it can. P01EE is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P01EE to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P01EE clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.