Indoor unit displays E0 and will not respond to remote or front panel buttons

Safety first: Turn off the Camry air conditioner at the wall isolator or circuit breaker and wait at least 5 minutes before touching any wiring or internal components.

Step-by-step:

• 1. Power reset: Disconnect power for 10–15 minutes to allow the indoor PCB to fully discharge. Restore power and check if E0 clears.
• 2. Check supply voltage: Use a multimeter (qualified persons only) to verify correct mains voltage at the indoor unit’s terminal block. Low or fluctuating voltage can corrupt EEPROM data.
• 3. Inspect wiring harness: Remove the indoor front cover, locate the main control PCB, and ensure all multi-pin connectors are fully seated and free of corrosion or burn marks.
• 4. Look for board damage: Visually inspect the indoor PCB for swollen capacitors, burnt tracks, or insect damage. If present, the board should be replaced, not repaired in the field.
• 5. Attempt reset procedure: Some Camry models allow a service reset via a small reset button on the PCB. With power off, press and hold the button, then restore power and release after 5–10 seconds (refer to the specific model’s service manual).

When to stop: If E0 persists after a power reset and connector check, do not continue powering the unit repeatedly. Contact a qualified Camry service technician to replace or reprogram the indoor main PCB.