U4

Outdoor Thermistor Open/Short Circuit

Description

One of the outdoor unit's temperature thermistors has an open or short circuit, preventing accurate temperature monitoring.

Appliance Error Codes Details

Error Code
U4
Error Name
Outdoor Thermistor Open/Short Circuit
Appliance Type
air_conditioner
Brand
Mitsubishi
Severity
medium

Additional Troubleshooting

1. Power cycle the unit
2. Check the outdoor thermistor connectors on the outdoor control board
3. Contact service to measure thermistor resistance and replace as needed

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Author: Pavel Volkov
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