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B3891 Code – Trailer Fog Lamps Circuit

What are the Possible Causes of the Code B3891?
  • Faulty Trailer Fog Lamps
  • Trailer Fog Lamps harness is open or shorted
  • Trailer Fog Lamps circuit poor electrical connection
  • Faulty Trailer Lighting Control Module
  • Need help with this OBD II code? Our mechanics are available within west Michigan to help. Outside of our service area? Visit our Car Help Section where you can ask questions and get answers.

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