AC compressor Disengaging

-KingJames- · 03-30-2021, 05:06 PM

If it is a faulty high pressure sensor, a poster above recommended NOT to change it w/o discharging the system first...ughh

The BMW dealership is the one that charged the system with Freon. You think they may have messed up by over filling or something? Maybe I can see if they can take a second look at it.

Wgosma · 03-30-2021, 05:21 PM

if you go back to Dealer, ask those guys if they verified the pressure sensor and other system components were checked for proper operation....they already told you the compressor is at fault, maybe it is....or maybe Mr Dealer wants to sell you a nice expensive compressor

....if you get anything less that a straightforward answer, find a reputable independent German shop or a/c specialist and take the car to them for 2nd opinion.

It's possible they over-filled, but we know the sensor is another possible cause for problem you're seeing. You need shop to pinpoint root cause.

If you remove sensor you likely opening the system to atmosphere, i.e. you lose refrigerant.

-KingJames- · 03-30-2021, 07:07 PM

Yeah i'll have to set up an appt with the dealer. Also I just rescanned the car (this time while the engine off but ignition ON) and there were no DTCs. Im guessing the 801224 code earlier may have only appeared plus a few others not related to the AC due to engine running which isn't recommended.

auburnf30x · 03-31-2021, 08:26 AM

One quick thing to check that I don't see mentioned...

It sounds like there's some other things going on, but just in case. Check your antifreeze in the low pressure auxiliary tank, it's the smaller of the two located at the front driver's side of your engine bay.

Mine had a slow leak, and the only way I found it was because when the level got too low, the compressor started rapidly short cycling in the same way you describe. Turns out it does that to protect the system and keep it from overheating. Refilled it, and runs fine. Cap is leaking pressure and vapor and will be replaced soon. I don't believe my scanner showed any trouble codes, but to be honest I'm not entirely sure I thought to check them until after the problem was fixed. Mine also would work perfectly when first starting the car cold, but once the system warmed up it would short cycle the rest of the drive.

Quick, cheap, and worth a look just in case.

Wgosma · 03-31-2021, 10:08 AM

Quote:

Originally Posted by -KingJames-

Yeah i'll have to set up an appt with the dealer. Also I just rescanned the car (this time while the engine off but ignition ON) and there were no DTCs. Im guessing the 801224 code earlier may have only appeared plus a few others not related to the AC due to engine running which isn't recommended.

If your car is not covered by warranty I would suggest at some point you get connected with a reputable independent BMW/Euro car shop- Dealers are almost always more costly on both parts and labor.

Parts buying: I'd be wary using EBay, places like FCP Euro have fair parts prices and offer Genuine BMW, OEM and aftermarket suppliers parts and they stand behind their products - best not to cheap out when buying parts for Bimmers.

Good luck/Bill

-KingJames- · 03-31-2021, 12:35 PM

Quote:

Originally Posted by auburnf30x

One quick thing to check that I don't see mentioned...

It sounds like there's some other things going on, but just in case. Check your antifreeze in the low pressure auxiliary tank, it's the smaller of the two located at the front driver's side of your engine bay.

Mine had a slow leak, and the only way I found it was because when the level got too low, the compressor started rapidly short cycling in the same way you describe. Turns out it does that to protect the system and keep it from overheating. Refilled it, and runs fine. Cap is leaking pressure and vapor and will be replaced soon. I don't believe my scanner showed any trouble codes, but to be honest I'm not entirely sure I thought to check them until after the problem was fixed. Mine also would work perfectly when first starting the car cold, but once the system warmed up it would short cycle the rest of the drive.

Quick, cheap, and worth a look just in case.

Well I had a total cooling system refresh. All coolant hoses and tanks and radiator/condenser are mostly new. The low pressure coolant tank was low a few times but I topped it off. I just checked it again and it was just under minimum. I just remembered that I used the old caps on the new tanks. You think buying a new cap should fix it?

auburnf30x · 03-31-2021, 02:49 PM

Quote:

Originally Posted by -KingJames-

Well I had a total cooling system refresh. All coolant hoses and tanks and radiator/condenser are mostly new. The low pressure coolant tank was low a few times but I topped it off. I just checked it again and it was just under minimum. I just remembered that I used the old caps on the new tanks. You think buying a new cap should fix it?

In my case it will...but the cap seems to be a weak point in the cooling system in these cars in general. Pressure test and oil analysis on mine showed no leaks, but the threads under the cap stay wet and my AC will start short cycling again after 3k miles.

Caps are $10 on RockAuto, so it's worth a shot anyway.

GOLDENDUSt86 · 04-19-2021, 01:15 PM

Quote:

Originally Posted by -KingJames-

Well I had a total cooling system refresh. All coolant hoses and tanks and radiator/condenser are mostly new. The low pressure coolant tank was low a few times but I topped it off. I just checked it again and it was just under minimum. I just remembered that I used the old caps on the new tanks. You think buying a new cap should fix it?

I’m having the same problem https://f30.bimmerpost.com/forums/sh...ght=Disengages
Had a coolant leak, replaced parts, and this happened with the same code.
Have put reached any fix???

-KingJames- · 04-21-2021, 12:30 PM

Quote:

Originally Posted by GOLDENDUSt86

I’m having the same problem https://f30.bimmerpost.com/forums/sh...ght=Disengages
Had a coolant leak, replaced parts, and this happened with the same code.
Have put reached any fix???

Not yet, haven't had time to take my car in to my mechanic since he's open on weekdays and i work on weekdays....

Are you getting those codes with engine off and ignition ON? Because I get no codes with just ignition ON and engine off.

-KingJames- · 04-29-2021, 02:53 PM

Conclusion: Went back to BMW dealer, they vacuumed out the charge and then charged it back up and it works perfectly now. They were the ones that initially charged it up and I'm guessing they may have over charged it since the pressure was high. I did not have to pay for the diagnosis or charge up since it was their mistake....

03-30-2021, 05:06 PM	#23
-KingJames- Private 9 Rep 60 Posts Drives: F34 GT Join Date: Nov 2020 Location: Self iTrader: (0)	If it is a faulty high pressure sensor, a poster above recommended NOT to change it w/o discharging the system first...ughh The BMW dealership is the one that charged the system with Freon. You think they may have messed up by over filling or something? Maybe I can see if they can take a second look at it.
	Appreciate 0 Quote

03-30-2021, 05:21 PM	#24
Wgosma Lieutenant Colonel 806 Rep 1,906 Posts Drives: 2012 F25 X3 28i (N52) Join Date: Sep 2018 Location: Northern Nevada iTrader: (0)	if you go back to Dealer, ask those guys if they verified the pressure sensor and other system components were checked for proper operation....they already told you the compressor is at fault, maybe it is....or maybe Mr Dealer wants to sell you a nice expensive compressor ....if you get anything less that a straightforward answer, find a reputable independent German shop or a/c specialist and take the car to them for 2nd opinion. It's possible they over-filled, but we know the sensor is another possible cause for problem you're seeing. You need shop to pinpoint root cause. If you remove sensor you likely opening the system to atmosphere, i.e. you lose refrigerant.
	Appreciate 0 Quote

03-30-2021, 07:07 PM	#25
-KingJames- Private 9 Rep 60 Posts Drives: F34 GT Join Date: Nov 2020 Location: Self iTrader: (0)	Yeah i'll have to set up an appt with the dealer. Also I just rescanned the car (this time while the engine off but ignition ON) and there were no DTCs. Im guessing the 801224 code earlier may have only appeared plus a few others not related to the AC due to engine running which isn't recommended.
	Appreciate 1 Wgosma806.00 Quote

03-31-2021, 08:26 AM	#26
auburnf30x Lieutenant 435 Rep 562 Posts Drives: 2017 BMW 330i xDrive Join Date: Jan 2021 Location: Auburn, AL iTrader: (0) Garage List 2017 BMW 330i xDrive [8.50]	One quick thing to check that I don't see mentioned... It sounds like there's some other things going on, but just in case. Check your antifreeze in the low pressure auxiliary tank, it's the smaller of the two located at the front driver's side of your engine bay. Mine had a slow leak, and the only way I found it was because when the level got too low, the compressor started rapidly short cycling in the same way you describe. Turns out it does that to protect the system and keep it from overheating. Refilled it, and runs fine. Cap is leaking pressure and vapor and will be replaced soon. I don't believe my scanner showed any trouble codes, but to be honest I'm not entirely sure I thought to check them until after the problem was fixed. Mine also would work perfectly when first starting the car cold, but once the system warmed up it would short cycle the rest of the drive. Quick, cheap, and worth a look just in case.
	Appreciate 0 Quote

04-29-2021, 02:53 PM	#32
-KingJames- Private 9 Rep 60 Posts Drives: F34 GT Join Date: Nov 2020 Location: Self iTrader: (0)	Conclusion: Went back to BMW dealer, they vacuumed out the charge and then charged it back up and it works perfectly now. They were the ones that initially charged it up and I'm guessing they may have over charged it since the pressure was high. I did not have to pay for the diagnosis or charge up since it was their mistake....
	Appreciate 0 Quote