If I start the engine with the AC ON (blower fan ON and AC ON) then my AC never works. However, when I start the engine with the blower turned to the OFF position and then start the blower when the engine is running, the AC seems to work most of the times. When the AC is working properly, it works really well.
That said, sometimes it will not blow as cold as it should. Like it is a little bit cold but not as cold as it can.
I can hear the compressor turning ON as well.
I have manual AC controls and I have refilled/checked the coolant level.

I'm thinking some sort of an electrical issue. Has anyone experienced this before?

 

I don't think it's an 'issue', but more of a 'design feature'!
While you are actually starting a Mini, a lot of things get turned off by the 'computers' - the A/C compressor is probably one of them.
There's also a short delay after pressing the snowflake button before the A/C kicks in.
I'd just turn the A/C off before you park the car.

AutoZone have an A/C recharge kit with a gauge on it - it's not a professional kit, but it will tell you whether a little refrigerant recharge is needed.

 

Most hot countries, the owners turn the AC off religiously before turning the car off, then turn it back on after they start the car. I found that such a bizaar practice and have never followed it. In theory it should not matter, what matters most is how long between turning hte ac off and back on. You should wait a minimum of 5 minutes between turning it off and on again for maximum life.

I would find the ac clutch relay and hook up a multimeter and seeing if the relay voltage is consistent with what your observed results are. That would indicate whether the problem is with the ac system or with the PCM. Basically splitting the potential issues in half. If it's PCM related, no need to mess with the ac system because once you get into that, it can get very expensive very fast. You don't want to do that only to find it's a PCM related issue. If it's a PCM issue, it can also get expensive, but you dont' want to go that route unless you've verified it's that.

 

The main issue is that the AC dosent work when I turn it ON after I start the engine. I have turned the AC off and then on again, dosent make a difference.
Like I said, I have refilled the refrigerant and the AC works well whenever it is properly working. Thats how I realized that its not working sometimes; it wont blow as cold as it does most of the times.

 

Thanks! I'll find that relay.

 

Have you checked the cabin air filter? I had problems with the AC working intermittently, the cabin air filter was really plugged up. Replacing the filter bought the AC back, it had worked fine ever since.

 

friend of mine with a 2004 recently had similar issue

had to replace the dash unit where some of the controls are .......

had taken it to a very good MINI shop who diagnosed the problem

 

 

Additional thought: it could be the A/C coil (on the compressor) which is essentially an electromagnet that engages the compressor clutch when activated. The coil, which is relatively inexpensive, can be replaced without replacing the compressor but the compressor has to be removed which is no small feat. ModMini has an excellent video on YouTube showing the entire process.

 

The A/C will not run unless the engine is running. The compressor draws too much power and will drain the battery if the key has been turned to the "accessory" slot, which is why it won't run unless the engine is running.

Many people turn off the A/C a few minutes before turning off the car to ensure that the system dries out before being shutoff. This is not just a mini thing, but prevents condensation, mold, and other nasty stuff from forming in the system. I don't do it myself, but that is why it is done.

Check the operation of your low speed fan. There is a sticky on the top of this forum that covers this situation. If you are standing still, or moving less than about 35 mph, you need an operational low speed fan to get the best A/C performance.