2004 AUDI A8

4.2L V8AWDAUTOMATICgas
1 active safety recall on this vehicle — view recalls
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P0045moderate severityPowertrain

Turbo/Supercharger Boost Control Solenoid Circuit/Open

on 2004 Audi A8 4.2L V8 · AWD

What this code means

The PCM detected an open circuit in the turbocharger or supercharger boost control solenoid.

Symptoms

  • Check Engine Light
  • Loss of boost pressure
  • Reduced power
  • Limp mode

Common causes

  • Faulty boost control solenoid
  • Wiring damage
  • PCM failure
  • Corroded connector

Diagnostic steps

  1. Test solenoid resistance
  2. Inspect wiring
  3. Check vacuum lines
  4. Command solenoid with scan tool

Repair notes

Replace boost control solenoid or repair wiring.

Other Powertrain codes on this vehicle

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