My fiance bought a used 2015 chevy equinox about a year ago or so. Since then it had an engine replacement done due to a bad head gasket. Ever since the engine replacement, the ac compressor won't work at all and randomly the dash will either light up like a Christmas tree or the lights on the dash wont turn on at all, sometimes the speedometer wuits working, sometimes the vehicle will go into reduced power/limp mode, and sometimes the engine won't turn over at all. Any clues as to what could be causing the problems would be helpful. TIA.
Ill assume it worked correctly for a short period of time after you got it back from the mechanic.
If not this really should be on them to figure out.
The why doesn't matter unless the insurance company owns the repair shop.
Have you scanned the engine to see what codes are coming up? That may point you to the correct area.
Second check the battery voltage, a faulty battery can create havoc.
Third would be the ground as already mentioned.
The engine comes out the bottom, so they discharged the AC system, that could be that simple.
My recommendation, get a manual, and walk thru every connection there is on the engine and harnesses, don't skip the vacuum hoses.
But based on what you are describing this is most likely an electrical connection or 2 that is lose, or something failed during the transfer.
They may have even snapped a connector and it will just not stay in place.
Good luck
