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2018 TOYOTA COROLLA
1.8L I4•FWD•CVT•gas•2ZR-FE
3 active safety recalls on this vehicle — view recalls
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Repairs395Labor499Torque3375Fluid7DTC1638Battery1Maintenance0Recalls3
P0702high severityPowertrain

Transmission Control System Electrical

on 2018 Toyota Corolla 1.8L I4 · FWD

What this code means

The PCM detected an electrical fault in the transmission control system. This can cause erratic shifting or transmission limp mode.

Symptoms

  • Harsh or erratic shifting
  • Transmission limp mode
  • Check engine light on

Common causes

  • Wiring or connector fault in transmission circuit
  • Failed transmission solenoid
  • Internal TCM fault
  • Poor ground connection

Diagnostic steps

  1. Scan and confirm P0702 code
  2. Inspect transmission wiring and connectors
  3. Test transmission solenoids and sensors
  4. Check TCM power and ground circuits
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