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P023B

Charge Air Cooler Coolant Pump A Control Circuit Low

CAC coolant pump A control voltage below expected range. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.

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

Common causes

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

  • Wiring shorted to groundCommon
  • Connector pins corroded - high contact resistanceLess likely
  • Harness chafing through insulationLess likely

Parts involved

  • Cac Coolant Pump A
  • Pump Wiring

P023B 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.