OBD-II code · Powertrain (generic, extended)

P2A3B O2 Sensor Negative Current Control Circuit/Open Bank 1 Sensor 3

The control circuit for the wide-band oxygen sensor negative current pump on bank 1 sensor 3 is open. Pumping current cannot be applied for lambda regulation.

Is it safe to drive with P2A3B?

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

Common causes

  • Most likelyOpen in pump current wire
  • PossibleInternal open in pump cell
  • Less likelyPin pushed back out of connector body

Symptoms

  • Check engine light on
  • Increased fuel consumption
  • Possible rough idle or hesitation
  • Failed emissions test

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.5–3 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Oxygen Sensor B1s3, Wiring Harness, Ecm

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