Obdaryn

P26F2Starter Relay B Stuck On

  • Generic OBD-II code · Powertrain
  • Turns on the check-engine light
  • Matters for the ITP
How the car detects it
P26F2 concerns the second starter relay, which on stop-start vehicles may engage the pinion of a tandem starter (GM) or form the second switching path of a two-relay layout (FCA Starter Control 2). The code means relay B fails to drop out after its command ends. Depending on wiring, the pinion may then remain in mesh, or the starter could be energised as soon as relay A closes. No manufacturer documents P26F2 publicly; the GM tables only cover the electrical driver faults of relay B (P26E4 to P26E6), and FCA bulletins tie Starter Control 2 to plausibility faults. Welded contacts and a control line fed from elsewhere are the obvious suspects. Driving on with this fault risks damage to the pinion and the flywheel ring gear.
What you may notice
  • Grinding or whining from the starter after the engine runs
  • Check engine light, stop-start unavailable
Likely causes
  • LikelyContacts of relay B welded or stuck
  • PossibleControl line of relay B fed from another circuit
  • RarePinion solenoid of the tandem starter sticking mechanically
Inspection (ITP)
Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
Repair
Medium · Usually a job for a workshop.Typical cost: €30 – €800

Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.