The most common reasons for similar threads end up being faulty low side sensors or wiring (my case a faulty connector), the aux fan situation or a problem with the variable compressor.

Since it's coming on but being commanded off: can you read the low pressure value and what is the Ω reading across the low pressure sensor

The other sensor that disables the system outright without any error is the temp sensor I think on the evaporator. The system is designed to inhibit operation when below some ambient temperature (so could be the reading of the ambient temperature also).

Make sure aux fan runs (command on with scan tools, or I think you can unplug a sensor wire I forget which but somebody here will chime in. Also when you first then key on I think the fan should turn like 1/3 of a turn).

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)