F15 air suspension issue

[abdul642]

Hi all

My air suspension is acting very weird. One side of the car is raising itself really high while the other side is keeping itself at correct height.

The air bellows both have been changed to brand new Arnott
The compressor was also changed
The ride height sensors have been changed (brand new from BMW)
The EHC control module also has been changed

Has anyone else encountered this problem? No garage can seem to find the issue

[scotty339]

Seems like the PN for the level sensors (37146870200) is the same for all 4 corners, with the difference being the brackets.

I'd try swapping the rear sensors, just in case.
I'd also re-bleed the air system using ISTA.

No codes?

Was it doing all of this before you swapped the 4 things mentioned, or did this happen as a result of one of the things?

[abdul642]

Originally Posted by scotty339

Seems like the PN for the level sensors (37146870200) is the same for all 4 corners, with the difference being the brackets.

I'd try swapping the rear sensors, just in case.
I'd also re-bleed the air system using ISTA.

No codes?

Was it doing all of this before you swapped the 4 things mentioned, or did this happen as a result of one of the things?

It's had brand new sensors in the rear for both sides.
The initial problem was one side was sagging. Found to be the bellows had a leak so both sides were changed and since then one side has kept raising itself. After that compressor, sensors and control unit all were changed but car still keeps raising itself.
Bags have been bled out and refilled numerous times and ride height levels reset on the computer but as soon as it's taken for a drive this issue arises.

[abdul642]

This issue has now been fixed. It turns out the aftermarket valve which goes onto the compressor has a red dot on top indicating the red tube should go onto that side (on OEM it's a blue dot so blue tube goes into this side)
Switched the tubes round and car is driving perfect now
So for anyone buying the aftermarket valve or compressor make sure you check the coloured dot on top and plug in the corresponding tube.

[tlow98]

Appreciate the follow up here. Seems annoyingly logical :-) glad you got it sorted.

[Sabs1815]

Were you getting a chassis error after you replaced the Valve and Compressor with Aftermarket? Im pretty sure I put the tubes in the correct places but I keep getting a chassis malfunction and ISTA is reading a short on the discharge valve.

The chassis malfunction is stopping the compressor from working on its own although If I try to fill the bags through the ISTA service function everything is responding as it should and the bags are holding up.

[abdul642]

Originally Posted by Sabs1815

Were you getting a chassis error after you replaced the Valve and Compressor with Aftermarket? Im pretty sure I put the tubes in the correct places but I keep getting a chassis malfunction and ISTA is reading a short on the discharge valve.

The chassis malfunction is stopping the compressor from working on its own although If I try to fill the bags through the ISTA service function everything is responding as it should and the bags are holding up.

You may need to check your fuses. I had a fuse blown but I can't be sure if that was the cause of the chassis control error

[MikeM6]

Originally Posted by Sabs1815

Were you getting a chassis error after you replaced the Valve and Compressor with Aftermarket? Im pretty sure I put the tubes in the correct places but I keep getting a chassis malfunction and ISTA is reading a short on the discharge valve.

The chassis malfunction is stopping the compressor from working on its own although If I try to fill the bags through the ISTA service function everything is responding as it should and the bags are holding up.

Did you ever figure out what the issue was? After replacing my compressor it didn't fill the bags, so I also used ISTA. Still getting the chassis malfunction error I had before the compressor swap, and the short on discharge valve code. I also see the transport mode code in ISTA. I can clear codes, but they keep coming back.

The vehicle appears to be at the correct height, and the ride seems normal, but I currently have the discharge valve short code. We'll see what happens the next time I drive it.

[skookumchuck]

My problem is similar to yours. the airbags kept going down also it was blowing a 40amp fuse (no. 110 ) i would replace that and up would go the air bags then blow the fuse. i replaced the airbags as they were leaking and it was still happening. I also the noticed on the screen in the car would say " chassis function restricted. can drive . see service centre ) after a while the compressor pump stopped working and the airbags wouldn't pump up. i replaced the air compressor and the regulator but still didn't work. Tested both the old pump and the new one and both work. I manually pumped the air bags up by attaching a battery and wiring to the connectors at the compressor pump and pumped up the air bags. They are still up. Next i took off the positive battery terminal and touched it to the neg terminal for several minutes to clear the codes. So far the fuse hasn’t blown like it used to. I'm at a loss as to why it kept blowing fuses and why the compressor stopped working. Once the air bags go down i have to get under the car, take off the plastic cover pull the compressor plug off and attach a battery to blow the air bags up ! it's a real pain I tell you. I have to use a mates pit to do all this and he's miles away. If anyone can shed any light on my problem I'd really appreciate it. I live 400km from the city and i'm going to see a bloke there to check the codes. BMW service centre were useless last time.
took it over the pit and took off the cover for the compressor and pulled off the power plug to the compressor and wired it so the wires go up through to the engine compartment. one wire to an earth bolt and the other free so that i can connect it to the red positive cap that is for jump starting. now when it goes down i just connect that and it starts the compressor. when it reaches a good height i disconnect and its stays up for a few weeks. need to find a circuit diagram for the compressor so i can trace back as to why i m not getting any power to it.