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

P2602

Coolant Pump Control Circuit Open

The ECU detects an open circuit on the electric coolant pump control line. Without pump control the engine cannot actively manage warm-up and cool-down phases.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number6 / 02

Possible causes

  • Pump motor open high
  • Drive line open medium
  • Pin pushed back out of connector body low

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 120–700 €
  • Estimated time: 0.5–2.5 h
  • Component: electric coolant pump
  • Component: coolant pump 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