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2.7L I4 2TR-FE•RWD•AUTOMATIC•gas•2TR-FE
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P0991moderate severityPowertrain

Transmission Fluid Pressure Sensor/Switch F Circuit Intermittent/Erratic

on 2016 Toyota SW4 2.7L I4 2TR-FE · RWD

What this code means

The signal from transmission fluid pressure sensor F is dropping out or jumping around instead of staying steady. This usually points to a loose connection or a failing sensor.

Symptoms

  • Erratic or harsh shifting
  • Transmission warning light on
  • Intermittent limp mode

Common causes

  • Loose or corroded sensor connector
  • Damaged sensor wiring
  • Faulty pressure sensor F
  • Low or contaminated transmission fluid

Diagnostic steps

  1. Scan for stored and pending codes
  2. Inspect sensor connector and wiring while wiggling
  3. Monitor pressure sensor data during a test drive
  4. Replace sensor if signal drops out under known-good wiring

Other Powertrain codes on this vehicle

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