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Pcm Code EO90, VCC Brake Switch Input Problem: Action:

PCM will set Code EO90 and turn on SERVICE ENGINE SOON light.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. Ensure continuity exists across VCC brake switch terminals with brake pedal released. If continuity does not exist, adjust or replace switch. Switch is located on brake pedal linkage. Check continuity of VCC brake switch circuit between brake switch, terminal "A" of transmission connector and terminal C4 of PCM connector. If switch and circuit are okay, problem is faulty connections at brake switch or PCM, or faulty PCM.
Fig 1: PCM Code EO90, Schematic, VCC Brake Switch Input Problem
G91F07631
Fig 2: Flow Chart, PCM Code EO90, VCC Brake Switch Input Problem
GB0022560