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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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Repairs0Labor1040Torque1596Fluid17DTC3336Battery2Maintenance0Recalls5
P0940moderate severityPowertrain

Hydraulic Oil Temperature Sensor Circuit Low

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The hydraulic oil temperature sensor signal is lower than expected. This usually results from an open circuit or grounded wiring.

Symptoms

  • Transmission warning light on
  • Poor shift performance
  • Incorrect temperature data

Common causes

  • Faulty oil temperature sensor
  • Open or grounded wiring
  • Loose connector
  • Control module fault

Diagnostic steps

  1. Retrieve diagnostic codes
  2. Inspect wiring for open or ground fault
  3. Check connector integrity
  4. Measure sensor resistance
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