OBD-II code · Powertrain (generic, extended)

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.

Is it safe to drive with P2A4B?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyTemperature sensor failed
  • PossibleWiring or connector fault

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.3–1.5 h
Emissions test
Likely to fail
Parts involved
Alt Fuel Temperature Sensor, Wiring Harness, Afcm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.