The lesson learned from all of these threads is if your air bags start leaking, replace them ASAP before the compressor fails... I wish I had known that from the beginning.

i got your PM, but the inbox needs to be cleaned up before i can respond there...

the INPA is a good one to try to see how the EPC2 works, you can even raise it there, lower it, put in to transport mode...

but your USB cable needs to connect to the right port - depending on how your computer is configured, you might need to manually adjust the port settings - on mine, it was trying to connect to COM3 but i changed it manually to COM1 and it started to work, even though the computer was saying something, like, the port is occupied, blah blah blah...

Try the port setting for the cable, and it should connect... once you connect, you will be able to read the codes

I've been reading a lot of threads about the air ride suspension and I am still ok since my system doesn't drain or leak and will fill up if I load the back with a lot of weight. So mainly I have a annoying Inactive leveling suspension blinking in my face ! So I purchased a new cord and P.A.software I should get that sometime next week. Hopefully I can get the new cord to work my cord has a chipset of RT232BL and all the cords I have seen are RT232RL maybe this is my problem. My Inpa software is installed and looks like it working but when i plug into the car the cord lights up but the ignition light on Inpa does not change. Thanks for your help

sockethead Thanks for the info on the airbags and compressor now every time I come out of my house or work I am looking at the height of my car.(Paranoid)

same
my buddy with a scanner told me my front left bag is leaking slightly
i watch the damn ride height everytime i walk up to the car

it raises about every 3 weeks
SLS light is one last owner just installed a new compressor

Sorry guys but a little paranoia is better than a big repair bill, eh?

Just updating... We finally got around to replacing the module and finally after a year and a half, there are no suspension errors and everything works as it should... No more TPMS light either!

Great thread, SLS and TPMS on in my truck
 

This system is just killing me... Documenting here, hope it helps others.

I have been trying to troubleshoot this for awhile now. Using an Autel DAS708 that can read codes, live data streams, and actuate all systems independently (kinda cool to raise and lower each corner). The error code I get is "Plausibility" for the level sensors. The front left sensor is reading 4.68V and shows no change when bouncing the suspension. All others between 1.68-2.4V. What does this mean: The truck thinks that the corner is at -163mm of ride height deviation! It basically shuts down the system (try to correct that and watch the bag go BOOM!).

Started working on this when I found the CV joint and seal on that side are bad and oil was everywhere (sensor killed by that? _no_)...

The list of replacements so far:
1) Both CV axles and seals
2) Rear right bag blew (audible) while jacking up the front. Replaced both rear bags with Arnott sport suspension bags. Careful with the clips, lost one and can only be bought in a bag of 10 (have plenty of spares).
3) Front left bag leaking after replacing rears... Replaced both with Arnott sport bags, very nice machined pieces and good prices.
4) Replaced front left sensor. Still reads 4.6V but at least shows a voltage change when bounced.

So... Wiring looks okay (would expect low/no voltage reading if bad connection). When I am looking at the wiring diagram in the Bentley manual I see the sense wire for the front is the only unique connection. It goes to the EHC 2 module, electrical symbol for BJT transistor connected to emitter...

Looks like a module swap is next based on what I have read here. Has anyone here ever tried repairing an EHC 2 module? I am willing to give it a try (did my own GM5 repair in the 330Ci). Will update when I know more.

dumb question, but what does water or moisture in the battery compartment mean?i noticed water in there when I checked my battery a few days ago...i also have sls inactive message .my battery is insufficiently charged according to the black color displayed in the little window on the top of the battery.
My car sat for a few months prior to sale so the SLS inactive might actually be solved by a new battery(which dealership already purchased-waiting for monday to bring it in..) but if a have a leak in there too where does it come from?can the compressor be bad too?whats the bulky thing on top of the battery?
sorry not familiar with all the stuff on my car yet..

water next to electronic modules = bad...

most likely the sunroof drains are clogged and a result, the water is getting in the sidepockets and the battery compartment... do a search on the forum for clogged drain lines.. .in general, folks were able to blow the lines with compressed air and even use gas water, like seltzer... i find the seltzer method cool!!! :nanana:

the bulky thing on top of battery could be the pyro charged positive terminal, or the air suspension pump - hard to tell what you are referring to...