JuanMR

Hey guys, for a couple days now my airmatic pump has not been working. I started by checking the relay, and it was bad, so I installed a new one and nothing. Then I jumped a wire straight from the batt to the motor and it staretd working. I removed the relay to check the wires coming upto its receptical, which has two thick red wires and two thinner wires. One of the red ones goes to the motor, the other I assume is the power supple to the relay and both of the thinner wires have positive voltage. The ground going to the motor is good and the motor read .3 ohms, should be good. Thinking a fuse might be blown, I checked every single fuse I can find and all are good. I applied direct voltage from the batt to the red wire at the relays receptical that goes to the motor, and it started working. So my guess is that the motor is good and something is stopping the power suppy to the relay. When I press the raise the car, nothing happens. The rear right side is the lowest, like basically on the ground. The left side is pretty much at the sme level, both front and back. I have no idea what else to check. Any ideas or personal experiance with this issue?

E55Greasemonkey

The power is supplied by a 40amp maxi fuse. Did you remove that fuse and look closely at it? Typically the relay burns when the pump is drawing too much amperage. Your pump may be on it's way out.

Blk04e55

Have you tried doing a burnout?

JuanMR

Where is that fuse at? I have checked every fuse at every fuse box I can think of.

JuanMR

Will that fix it? Lol

E55Greasemonkey

I think it's in the passenger footwell in the power distribution box. I'll have to check the wiring diagram later.

FASN8N

Check the fuse chart here
https://mbworld.org/forums/5522729-post1.html

desired_speeds

passenger footwell - fold the carpet down, remove black foam piece, remove 3 10mm plastic nuts, fold metal panel forward, take out the white felt piece and its right there. Refer to fuse chart above to find the correct fuse.

JuanMR

Found the fuse! Was blown. Changed it and wala! Thank all of you for your help, greatly appreciate it. Now I can go back to winning races. Lol

E55Greasemonkey

And don't forget about that burnout.

JuanMR

[QUOTE=E55Greasemonkey;5597622] And don't forget about that burnout.[

Done! Will need new tires after today.

urbamworm

I am struggling to figure out airmatic issue myself. I had been having the rear of car slamming very shortly after the car was turned off and when stared it would struggle to raise then finally go up and then came to the point it didn't want to raise anymore. I could hear air leak from passenger rear bag toward bottom of bag so assumed I needed to replace the bag. I had a spare set of used bags I bought when I purchased the car 6+ years ago so figured no big deal, time to put one in. The compressor on the last few days leading up to this seemed to not always turn on when car was started and hitting the raise/lower button didn't help, shutting car off and turning back on didn't help either except for sometimes it would decide to work.

Moving on I install one of the used bags and fire the car up to see if it is all fixed and the compressor wouldn't turn on. I figure the compressor must have gave up, I pull it out and hood power and ground to it using a drill battery and it turns right on. I disconnect the power from it and then reconnect a few times and it would turn back on a few times then it wouldn't fire up anymore, at this point I ordered a new compressor off Ebay, it comes in and I install it, fire car up and again the compressor doesn't turn on. I checked the fuse in driver side panel at end of dash and it was good, I checked the big orange 40am fuse under hood and it was good, I checked the relay hitting power and ground to it with the drill battery and it clicked and also checked continuity to the other poles of it with a multimeter and it all seemed good. I pulled the relay harness plug up as far as I could out of the fuse box under the hood and I see constant power using a test light at the position that pin 30 of the relay plugs in to, I hooked the test light to power on the post with nut right by the relay and checked the positions that pins 85 and 86 go to on the plug for ground which has 2 small wires coming in the back of it and I get no ground at either of those with the car off and with engine running. I assumed the ecu must send a ground signal to those to activate the relay to shoot power over from pin 30 to the other side to pin 87 to fire up the pump. I halfway looked at the fuse under passenger footwelll area also but assume that is the fuse that sends power to the fuse box under the hood where I am seeing power at pin 30 of the relay harness plug so figure everything is good in the fuse and relay department, just not sure about the pins 85 and 86 not getting signal in the relay harness plug.

I jumped power across the relay plug from pin 30 to pin 87 position with the car off and with engine running and the compressor turns right on when I jump power but it just sits there and runs that the car does not raise, it is slammed and doesn't budge even if I run the brand new compressor for 30 seconds and I hear no leaks anywhere. I figure the compressor is creating pressure but it isn't being sent out to the 4 corners of the car due to something else going on with valves or something but no clue what to check. Only thing I can say is the electrical connector on that passenger rear bag I replaced wouldn't lock in to place but it was pushed on to the plug on the bag, not sure if that could be causing an issue with the car not wanting to raise even when the compressor has power jumped to it. But that is a whole different problem from also not having the compressor come on by itself.

Any ideas?

ap10046

I'm not saying this issue may be the same as yours, but check the level sensors. 1 rear 2 front. I had the same issue and disconnected the tubing to the bags and inflated with an air compressor, all worked fine, no leaks, car was going 1 side up and other side down, front down, rear up and weird things. No fault codes, nothing. Was the damn level sensors that had popped out of the socket. The plastic gets old and brittle and cracks.

P.S. urbamworm, love your wheels. What make are they, please?

urbamworm

It had a bunch of codes that I cleared, one comes back about right rear connection open. The connector to the right rear air bag that I replaced didn't seem like it wanted to clip in place, I just pushed it on. Apparently that must not be making contact right, not sure if that would cause the whole system to not work or not, need to mess with it more.

Wheels are 20" Vossen CV7. Actually need a replacement front one since I hit a bad pothole and bent one.

urbamworm

Jacked the car up and played with the electric plug connector for the air bag that was swapped out. Dropped it back down to the ground and fired the car up and the compressor kicked on and car aired up. Driver front is a little high, not sure why it didn't level it out but haven't driven car out of driveway. The swapped bag is leaking air somewhere, I can hear it coming from that area, just not sure if the used bag that has been sitting in the shed for 6 years is also bad or if the reservoir hose is not secure enough but I have a feeling it is the bag itself most likely which sucks. So good news is it seems that all electrical connections must be good or the air compressor won't work and let air to each corner of the car, bad news is I have more work ahead to figure out this leak and probably have to buy a new bag or I think the Arnott come in a set, haven't researched yet.

bbirdwell

Stop screwing around with one part at a time. Replace the air springs. All of them. Bite the bullet, do it one time. When you go in to rebuild a sub-system, you rebuild the entire sub-system and accept the cost. I'm not trying to be a d**k, just trying to reduce your pain. Your time is money; spend money up front to reduce the amount of time you spend replacing parts.
Replace all air springs as I did. In my case, problem solved. If still a problem, verify/replace sensors. After that, replace compressor. After that, valve block. After that, airmatic module. After that, buzzing out every individual wire.
How in-depth do you want to go?
Also, you need to calibrate your suspension whenever you perform major work on it. Such as replacing the air springs. I've posted DIYs on this but you need a STAR/Xentry system and an inclinometer app on your cell phone to perform this. If you don't want to spend the money on the equipment, then pay the dealer. Seriously.
Best of luck to you.

urbamworm

Thanks for the dick response lol. I have 2 Arnott replacement air struts in the front already from when the front failed. One fixed and then years later the other fixed and the air bag I put on was one from a used set I bought over 6 years ago when I bought the car, why would I not try to install one to fix the issue vs buying 2 new front air struts again and 2 new air bags, are you serious LOL.

211.070

David, if you go with Arnott they say that both rear should be replaced together. Also if you replace them with new factory components it would be foolish to drop the subframe to replace only one.

urbamworm

You don't have to drop the sub frame to replace the bag, I unbolted 2 parts at the lower control arm and pulled it right out. Car leveled itself out in the front after I drove the car but the old bag I had laying around was leaking so bought a new one off ebay for like $160 from aftermarket company, that comes in tomorrow and will be installing. Few other little issues will be fixed soon and hopefully in the next month or so the car will be sent to a new home.

arnottdoug

You'll want to replace both rear air springs at the same time if replacing with Arnott. In order to not need the reservoir and save you from having to drop the sub we made the piston a different size. If you only replace one - the level sensors will make one of the springs a different height.