OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P01E6

Engine Coolant Temperature Sensor 3 Circuit High

ECT sensor 3 signal voltage above expected range. The engine coolant temperature sensor feeds warm-up enrichment, fan control and closed-loop entry — a stuck-cold reading keeps the engine in open loop and rich forever.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / E6

Possible causes

  • Signal wire open high
  • Connector pins corroded - high contact resistance low
  • Supply wire pinched against B+ source low

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

Inspection / repair

  • Difficulty: easy
  • DIY: possible
  • Estimated cost: 40–250 €
  • Estimated time: 0.3–1.5 h
  • Component: ect sensor 3
  • Component: sensor wiring
  • MIL / check engine light
  • emissions-relevant

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication