OBD-II code · Powertrain (generic)

P0623 Generator Lamp Control Circuit

Generic generator warning lamp control circuit fault, often used where the lamp terminal designation is not L or where multiple lamps share a single output.

Is it safe to drive with P0623?

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

Common causes

  • Most likelyLamp circuit open or shorted

Symptoms

  • Check engine light on
  • Possible limp mode or no-start
  • Multiple follow-up faults across modules
  • Reset/relearn may be needed after repair

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
0.5–2 h
Emissions test
Usually unaffected
Parts involved
Alternator, Alternator Wiring

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