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

P0119

Engine Coolant Temperature Sensor Circuit Intermittent

The ECU detects intermittent signal dropouts on the engine coolant temperature (ECT) sensor circuit. Fault not constantly present, typically due to loose connector, chafed wiring or a sensor failing thermally.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / 19

Possible causes

  • ECT connector loose or corroded high
  • Sensor fails when warm medium
  • Wiring chafed near hot engine parts medium

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: 30–150 €
  • Estimated time: 0.3–1 h
  • Component: ect sensor
  • Component: ect connector
  • Component: ect wiring
  • MIL / check engine light
  • emissions-relevant
  • drive cycle required

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