OBD-II code · Powertrain (generic)

P0231 Fuel Pump Secondary Circuit Low

The voltage on the secondary side of the fuel pump circuit is below the expected level when the pump is commanded on. Often caused by a failed pump motor, corroded ground, or wiring fault.

Is it safe to drive with P0231?

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

Common causes

  • Most likelyFuel pump motor failed or worn
  • PossiblePump ground point corroded
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light on
  • Hard start, no start, or stalling under load
  • Power loss especially at high load or rpm
  • Possible long cranking time

Repair at a glance

Difficulty
Medium
DIY friendly
Often, with basic tools
Typical labour
1–4 h
Emissions test
Usually unaffected
Parts involved
Fuel Pump, Fuel Pump Wiring

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