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1998 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1042Torque1610Fluid17DTC3334Battery2Maintenance0Recalls5
P0699high severityPowertrain

Sensor Reference Voltage C Circuit High

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The sensor reference voltage circuit C is reading above the expected 5 volts. This often points to a short to voltage in the reference circuit.

Symptoms

  • Check engine light on
  • Multiple sensor codes
  • Erratic sensor readings

Common causes

  • Short to power in reference wire
  • Faulty sensor
  • Corroded connector
  • Faulty PCM

Diagnostic steps

  1. Verify high reference voltage with meter
  2. Check wiring for short to voltage
  3. Disconnect sensors to isolate fault
  4. Repair wiring or replace PCM
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