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2003 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas•3RZ-FE
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1066Torque2197Fluid17DTC3480Battery2Maintenance0Recalls5
P0651moderate severityPowertrain

Sensor Reference Voltage B Circuit

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

The PCM detected a fault in the B sensor reference voltage circuit. Multiple sensors sharing this reference may report inaccurate values.

Symptoms

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

Common causes

  • Short in reference voltage circuit
  • Damaged wiring or connector
  • Faulty sensor loading the circuit
  • PCM internal fault

Diagnostic steps

  1. Read all stored codes
  2. Inspect reference circuit wiring
  3. Measure reference voltage at sensors
  4. Isolate faulty sensor or PCM
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Other Powertrain codes on this vehicle

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