OBD-II code · Powertrain (generic, extended)

P2605 Intake Air Heater B Circuit / Open

The controller cannot drive the secondary intake air heater (heater grid B) used on diesel engines for cold-start support. The grid stays cold so cold-start emissions and white smoke increase.

Is it safe to drive with P2605?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyOpen heater grid element
  • PossibleFailed heater relay or open coil

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.8–2.5 h
Emissions test
Usually unaffected
Parts involved
Intake Air Heater B, Heater Relay, Wiring Harness

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.