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

P0670

Glow Plug Module Control Circuit

The control circuit between the engine controller and the glow plug control module reports a fault. The module cannot reliably drive the glow plugs for cold-start preheating.

SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number6 / 70

Possible causes

  • Glow plug control module faulty high
  • Wiring or connector fault medium

Symptoms

  • Glow plug warning light on (often orange coil symbol)
  • Hard cold start or no start in cold weather
  • White smoke from exhaust during warm-up

Inspection / repair

  • Difficulty: medium
  • DIY: shop recommended
  • Estimated cost: 150–700 €
  • Estimated time: 0.5–2.5 h
  • Component: glow plug module
  • Component: module 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