2018 FORD FOCUS

2.0L I4 EcoBoostFWDDCTgasturbo
5 active safety recalls on this vehicle — view recalls
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B0123low severityBody

Hood Ajar Switch Circuit

on 2018 Ford Focus 2.0L I4 EcoBoost · FWD

What this code means

Malfunction in the hood ajar switch circuit used by the theft deterrent system and vehicle status monitoring.

Symptoms

  • Hood ajar warning always on or off
  • Theft system does not detect hood opening
  • Interior lights triggered by phantom hood open

Common causes

  • Faulty hood switch
  • Switch out of adjustment
  • Wiring damage in engine bay
  • Corroded switch from engine bay moisture

Diagnostic steps

  1. Check hood switch alignment
  2. Test switch continuity
  3. Inspect wiring
  4. Clean or adjust switch
  5. Test circuit voltage at BCM

Repair notes

Adjust or replace hood ajar switch. Protect wiring from engine bay heat and moisture.

Other Body codes on this vehicle

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