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1999 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1040Torque1596Fluid17DTC3336Battery2Maintenance0Recalls5
P0955moderate severityPowertrain

Auto Shift Manual Mode Circuit

on 1999 Toyota Tacoma 2.7L I4 · RWD

What this code means

A general fault has been detected in the automatic shift manual mode circuit. This covers the electrical circuit that enables driver-controlled manual shifting.

Symptoms

  • Manual mode unavailable
  • Transmission warning light on
  • Shift requests ignored

Common causes

  • Faulty mode selector switch
  • Wiring or connector fault
  • Failed transmission control module
  • Poor ground connection

Diagnostic steps

  1. Scan for stored codes
  2. Inspect mode circuit wiring and connectors
  3. Test selector switch function
  4. Check TCM inputs with live data
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