Another self level inactive question
 

I have a 04 4.8is with this famous sel level inactive on the dash. I have checked the 30 amp fuse and it was fine and I replaced it anyway also I replaced the relay.
So my truck is level no air leaks but the compressor has not come on in 2 weeks and it is starting to look like its getting lower in the back after 2 weeks. Can I actuate the relay to fill the airbags up to buy more time to troubleshoot. What is the best way to tested the level sensors. I dont have any water or any signs of moisture in the battery compartment and everything looks brand new like the compressor and control module.
Thanks
Craig

Ur control module is behind glovebox

My front bags leak a little bit, compressor kiks in 1 time in a month and my sls light is on

I thought the control module was right beside the battery ?

It depends on how your X is optioned. If you have the rear "single axle" (EHC I) suspension...then it is near the battery. If you have the "dual axle" (EHC II) suspension...then it is up front behind the glove box.

Which system do you have?

He has a 4.8is it only came with 2axle front n back air springs/bags

I have the dual axle so I will check out my connections behind the glove box today. Is there anyway to bypass the controller and run the compressor to fill the system up. maybe by the relay to the compressor. Also, what is the best way to test the level sensors to find out which one is bad.
Thanks again
Craig

Help us help you better by creating a signature that includes your model/model year/build date (or add it to the info that appears in the upper right). :)

There are multiple models, engines, transmissions, & other changes that occurred during the production run from the 2000-2006 model years that helps us respond with better answers (correct ones etc) as well as if we need to look up info/diagrams/part nbrs etc....which all require info/details. By not having this info, your posts may either get ignored, skipped over, or may take longer by having to ask for the info needed to respond...which again, can add time to getting the info you needed.

If you click the USER CP link at the top of the page, you'll see links to create a signature. :)

Sorry about that I thought I had that in there must have been E46 fanatics.

:thumbup: :thumbup:

I believe you normally check the sensor(s) voltage.

If you have access to a GT1, here are diagnostic steps on SLS Inactive:
http://www.xoutpost.com/916297-post4.html

If you have a leak (my guess), don't put off repairs too long or you will need to replace your compressor too.

well I jacked it up and looked at all the sensors everthing is connected and looks good. When I let it down it sounded like the compressor started and ran for a few seconds. I pulled the glove box and the connections look good there also. I am working on getting the software to work on old laptop I have Inpa installed and i get a error IFH-0018 when i try to connect

Make sure the sensor arms are positioned correctly as well. I got the Self Level Inactive message after changing the wishbone and connected the arm pointing in the opposite direction. D'oh!
That or one of your sensors took a crap?

Update: I still have the self leveling inactive on the dash. I checked out all the sensors and connections also the connections on the control module behind the glovebox. I came up with nothing out of the ordnary. So today i was loading up some stuff in the back and the truck was running and the compressor kicked on and i watched it lift the back of the truck up and the dash still has the stupid message on it. I am completely baffled now isnt that the leveing ? What do I look at next ?

Hook up to a GT1 diagnostic scanner and see what it tells you.

This is the only way to find out what's wrong with the system. DIS also has a diagnostic routine for TS the system...

Any chance that you get an occasional TPMS light on he dash?

Not to hijack... but we get that all the time and and self level suspension inactive... when we clear them, they both come back on. What does that mean? Bad module?
The dealer couldn't figure it out...We gave up like 6 months ago

Socket, that's exactly what happened to me. That's why I threw that question in there. The TPMS system is monitored by the EHC2 module (Electronic Height Control 2 Axle) and when the module faults, it can through the TPMS light. Mine would happen only after 45 minutes or so of sustained highway driving. After 3 months of pulling my hair out, killcrap (member on this site) said to look at the EHC2 module. Sure enough, he was right. It's pricey, $640, but it fixed the problem. Thank god for aftermarket warranties.

Yea we had a feeling it would turn out to be the module...damn it! We've already replaced the struts, rear bags, the compressor and the front right height sensor... they were all bad... not just parts swapping. I'll have to see if our aftermarket warranty will cover it. Thanks for the info. I really appreciate it

Module for EHC2 is like 500 more than the EHC module for rear air only cars, sucks.

The PO replaced it before I bought the truck since it was throwing faults, along with replacing both height sensors so that it was clear when he delivered it of faults and i thought it was fixed.

Went out the next morning, both air struts were leaked in front and message was active again, he neglected to mention the front air bags were leaking.

1300 later and the car held just fine, but my compressor was overworked from when the PO owned it and i needed a new one, found one used for 250 and my air suspension works flawlessly.


Sucks that a lot of these parts tend to go in "dominoes", hope you get it sorted out

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...

Hi four.8is. Exact same color and interior as mine. Beautiful trucks, just wish they were more reliable.

TerminatorX5 has given you the most common failure mode for the water in the rear (sunroof). As he stated there are a lot of electronics back there so try clearing those drains ASAP. In your case the module for the SLS is behind the glove box as 4.8is used EHC2 and have the front leveling as well.

The large black dome over the battery contains the SLS pump and valves. If you take the two bolts and two nuts off and flip it on it's side you will see these parts.

Hopefully the new battery clears the problem (BMW electronics well known for being flaky without really robust voltage levels). If not your best bet to is to find someone with a really good scan tool.

This very exact same thing just happened to me a week ago and I'm dealing with it now. It involves the same TPMS condition after 45 minutes of driving with the combination SUSP INACTIVE message.

I have a 2006 4.8IS, does that mean I have the EHC2? I'm looking at the diagram but it looks like I have the EHC1 because I have the pumpkin shaped Encapsulated Air Supply System. I am confused. What do I have?

According to Roadkill (which describes my exact situation with the TPMS and SUSP INACTIVE message) I should have the EHC2 based on his description above?
I've already pulled down the glove box if that's indeed where it is located and I ran into a plastic molded panel cover behind the glove box, is it behind this panel?

Also, for those who have replaced this module already, where did you get yours and is there a better alternative than the dealer?

BTW, already checked associated fuses front and back, they're all intact.



Thanks in advance everyone,
MANGO

2006, 4.8iS = air at all 4 corners = EHCII = EHC2

can't tell you where to get the module, though... :(

Thanks Terminator!
Appreciate the helpful info.



MANGO

My advise to anyone replacing this module is get it from the dealer. The part has a two year warranty when purchased from the a dealer... why do I say this? Because our replacement module also failed. Since it was bought and installed by the dealer, it was replaced and recoded at no charge.

Super info in here - spent ages chasing this issue and now knowing the TMPS is linked through the EHCII module I can be pretty sure I need a module !

Did all you guys get from the dealer or did you get cheaper online ?

Ive taken my modul apart and no signs of an damage etc but appears to be made by Wabco and has some part numbers on it ?

There was a guy in the UK ? That was repairing them a few years back when our module failed. I don't know if he's still around.
The modules are finicky & fragile and need to be coded and calibrated.
My advice is to take the hit and get it from the dealer. That way you get a 2 year unlimited mileage warranty on it.
We went through two modules in a year but since it was bought and installed at the dealership. The second one didn't cost a dime to have installed

Thats cool chap - a few people on the UK forum have some indepth knowledge of the systems but not as many as on here :(