My sons 05 Mini S had an AC freon leak which I repaired. AC works fine now. He contacted me on my way to work and informed me that his temp light had come on and he shot me a pic. I told him to pull over and shut it down. Couple hours later he drove it home (about 5 miles) and it didn't overheat again. My question is, would the AC issues cause the vehicle to overheat?? When I get home I will check the coolant and the oil, I was wondering if there is anything else I should be checking?? Possibly stuck thermostat I guess....

 

Yes it will overheat with the AC on. But only if the low speed fan is not kicking on. Normally when the AC is on this fan will kick on when necessary to keep the engine cool. Sounds to me like that is the problem. Check your fuses, but it is most like the low speed fan resistor that is not working.
Here is some great reading material
https://www.northamericanmotoring.co...-solution.html

 

You might also check that the repair shop plugged the fan back in after possibly having to disconnect or remove.
Not sure of the work necessary, but if they had to remove the radiator, maybe they didn't get the air bubble out when refilling. Turn the screw on the front radiator hose when it starts to warm up carefully to let the air pocket out.

 

One tip/suggestion...
If it happens again...sometimes when the crank pulley FIRST starts to fail...it will be OK till the AC is turned on..start to slip...causing the car to overheat. Then the car cools off...car is started, and is fine for a bit. It generally worsens over a few trips.
Basically the rubber on the crank damper starts to slip/tear....and under low loads, it is initially ok...but worsens quickly.
A repair shop SHOULD NOT have had to drain or touch the rad on a gen1 car to change the condenser. compressor, dryer, or recharge it with r134A, etc....

 

PS check for low coolant..the tanks sometimes leaks a bit....along the seam.