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2021 TOYOTA COROLLA
1.8L I4 Hybrid•FWD•CVT•hybrid•2ZR-FXE
1 active safety recall on this vehicle — view recalls
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Repairs0Labor495Torque3629Fluid7DTC1930Battery1Maintenance0Recalls1
P3475moderate severityPowertrain

EV/Hybrid Waste Heat Recovery System Fault

on 2021 Toyota Corolla 1.8L I4 Hybrid · FWD

What this code means

The waste heat recovery system that captures heat from the motor/inverter to warm the battery or cabin is not functioning.

Symptoms

  • Slower battery warm-up in cold weather
  • Cabin heating less efficient
  • Increased energy consumption for heating
  • Range reduction in cold conditions
  • Waste heat valve indicator fault

Common causes

  • Heat recovery valve stuck
  • Coolant crossover valve failure
  • Control module fault
  • Coolant circuit air lock
  • Temperature sensor error in heat recovery loop

Diagnostic steps

  1. Check waste heat recovery valve positions
  2. Monitor coolant temperatures in recovery circuit
  3. Command valve positions via scan tool
  4. Bleed air from heat recovery coolant loop
  5. Test temperature sensors in recovery circuit

Repair notes

Replace waste heat recovery valve. Bleed air from coolant circuit. Repair any coolant leaks in the recovery loop.

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