P0703 – Brake Switch B Circuit

Description

The ECM detects a malfunction in brake switch B affecting transmission control.

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Symptoms

  • Harsh shifting
  • Cruise control disabled
  • Brake lights issues

Causes

  • Faulty brake switch
  • Wiring issues
  • Poor grounds

Diagnosis

  • Monitor brake switch data
  • Inspect wiring
  • Check grounds

Repair

  • Replace brake switch
  • Repair wiring