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P2A4B

Alternative Fuel Temperature Sensor Circuit

The AFCM detects a generic fault on the alternative fuel temperature sensor. Fuel viscosity and density compensation cannot be applied reliably.

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

Common causes

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

  • Temperature sensor failedCommon
  • Wiring or connector faultPossible

Parts involved

  • Alt Fuel Temperature Sensor
  • Wiring Harness
  • Afcm

P2A4B 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.