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2002 TOYOTA MR2
1.8L I4•RWD•AUTOMATIC•gas•1ZZ-FE
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Repairs0Labor493Torque2151Fluid7DTC1720Battery1Maintenance0Recalls0
P0939moderate severityPowertrain

Hydraulic Oil Temperature Sensor Circuit High

on 2002 Toyota MR2 1.8L I4 · RWD

What this code means

The hydraulic oil temperature sensor signal is higher than expected. This is typically due to a wiring short or defective sensor.

Symptoms

  • Transmission warning light on
  • Erratic shifting
  • False overheat indication

Common causes

  • Faulty oil temperature sensor
  • Short to voltage in circuit
  • Corroded connector pins
  • Bad transmission control module

Diagnostic steps

  1. Scan for stored codes
  2. Inspect connector for damage
  3. Check circuit for short to voltage
  4. Verify sensor signal against spec
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