Mitsubishi Heavy Industries · Air Conditioners
A serial transmission error is detected, meaning communication signals between units are not correctly detected for 7 minutes and 35 seconds. This is a critical communication fault.
Click steps to track your progress.
Turn off the main power to the unit.
Inspect the serial communication lines for any damage, disconnections, or looseness, ensuring they are correctly connected.
Check for any external sources of electrical noise (e.g., other electronics, power fluctuations) that might be interfering with communication.
Ensure all connections are secure and undisturbed.
If all connections are sound and no obvious noise source is identified, the indoor or outdoor PCB may be faulty and require professional service.