Mini Countryman AC System Issue

Sounds like a classic A/C issue. The A/C compressor not kicking on could be a few things. Have you checked the pressure switch? Sometimes a faulty switch will prevent the compressor from engaging to protect the system. Also, is the error code related to low voltage specific to the A/C compressor circuit, or is it a general vehicle undervoltage code?

That's helpful. How would I go about checking the pressure switch? And regarding the error code, how can I determine if it relates specifically to the A/C compressor circuit versus general vehicle undervoltage?

Checking the pressure switch requires a multimeter and some knowledge of the A/C system's wiring. Best left to a workshop unless you're comfortable working with electrical circuits. As for the error code, a proper diagnostic scan tool should specify which circuit is reporting the undervoltage. If it's a generic code, it could be a wider electrical issue affecting the A/C system. Given the undervoltage diagnosis, it might be worth having a professional check the relay switch for the A/C compressor as well. Take it to the workshop and have them check the electrical system.

Just wanted to close the loop on this. Turns out the undervoltage diagnosis was spot on. The A/C system was shutting down due to a faulty relay switch. Replacement cost me 240€, and the air conditioning is blowing cold again. Thanks for the insights.