Powertrain, generic · Auxiliary emission controls

P0475 Exhaust Pressure Control Valve A

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

The exhaust pressure control valve is a flap in the exhaust: on older Navistar/Ford diesels a warm-up flap that raises back pressure when cold, on Ram and others an exhaust brake, on VW's 2.0 TDI a flap that drives the low-pressure EGR, and on Audi and Bentley a sound flap. P0475 is the general circuit fault of valve A, monitored like any output as CARB requires. VW's 2.0 TDI of 2015 sets it together with P0477/P0478, and the actuator electronics are replaced; Audi uses it for an electrical fault of the sound flap, Bentley for a shorted commutator in the flap motor. On the Navistar warm-up flap, a patent describes control to a target back pressure with the exhaust pressure sensor as feedback.

Likely causes

Flap actuator (motor or electronics) faulty
Wire or connector at the exhaust damaged or corroded
Control wire open
Driver in the engine module

Symptoms

  • Check engine light on
  • Flap without function: sound unchanged, rattling
  • Diesel: longer warm-up, exhaust brake weak or EGR faults

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€150–900
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

exhaust pressure control valve avalve actuatoractuator wiringengine control module

Related codes

P0476P0477P0478P0479P049F

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov, patents.google.com.