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P23A5

Exhaust Heat Exchanger Bypass Valve B Control Performance

Exhaust Heat Exchanger Bypass Valve B Control Performance: the component is electrically intact but its response does not match the command.

  • Check engine light: Yes
  • Emissions related: Yes
  • Repair difficulty: medium

Common causes

Ordered by how often each turns out to be the cause.

  • Flap stuck due to soot or carbonCommon

Parts involved

  • Exhaust Bypass Valve B

P23A5 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.