OBD-II code · Powertrain (generic)

P04D7 Exhaust Brake Input Circuit Intermittent or Erratic

Same as P04D3 with intermittent or erratic signal. The exhaust control valve modulates exhaust backpressure or routing (EGR feed, sound, regen support); a malfunction shifts torque mapping and may trigger limp mode.

Is it safe to drive with P04D7?

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

Common causes

  • Most likelyIntermittent contact at connector
  • Less likelyConnector with intermittent contact under vibration
  • Less likelyHarness routed against vibrating component

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
0.6–1.8 h
Emissions test
Usually unaffected
Parts involved
Exhaust Brake Request Switch, Exhaust Brake Wiring

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