2007 E550 Airmatic troubles and solution
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2007 E550 Airmatic troubles and solution
Good morning I have completed repairing the Airmatic system in my 2007 E550 Sedan ans since it was complicated and multi issued I thought I’d share it to maybe help someone else out in the future. I did a ton of searching and therefore didn’t need to ask any questions here but the final piece of information was not found here it was actually on a UK site.
So to begin I’ll say I’m not sure I ever heard my compressor run the three years I’ve owned this car. It may have been running off stored pressure. That may not be possible as I was able to raise and lower the car. Ok so we will start from the first problem I was coming home and started getting a bad molten plastic smell no compressor noise but a hot bad smell. I thought that was odd and it was coming from my left headlight. I couldn’t figure out what was up until I got a message on my dash that Airmatic had a leak. I did some googling and realized that’s where my compressor is so I went home and parked it. Did some trouble shooting discovered the compressor wasn’t running. Checked the relay with a 9v battery it worked ordered a compressor. Ok now it gets fun. I unplug the relay and drive to work where I can use my lift. It rides like coil overs on a Honda it was pretty stiff. Ok get it on the lift pull the compressor and find the power connector was melted together. I break it apart but now I’m fixing the harness. Order the factory plug and pins from the dealer finally get that two days later solder in a length of new wire because my wires had melted near the plug. Get it all back together pretty and lower it down and...nothing works. WTF. I jump the relay compressor works but car won’t raise. ? I drive it home. Get a malfunction message and it’s riding a little soft. At home I realize the entire circuit is dead. ? I use a jack pull the wheel and fender liner no power at the compressor. Everything else looks good even the control plug has the correct voltage. But my big 40 amp fuse has no power I pull the fuse block expecting to have some molten wires but all is good so what’s going on?. This is where I’m about to torch the car when I find an old post in a UK forum. There’s a pre fuse box under the passenger floor. Sweet I pull back the carpet unscrew the cover and there it is a blown 40 amp maxi fuse. Change that reassemble and EVERYTHING WORKS!!! Redemption. I drive to the liquor store and get out and the compressor is running. And won’t stop. 😡. I pull the relay, getting pretty good at it at this point, and realize where this all started. My relay gets stuck when hot and causes all the other problems, burnt compressor, melted wires, blown fuse. I run down to the auto part store get a new relay plug it in boom no more problems. 👏🏻😁
So to begin I’ll say I’m not sure I ever heard my compressor run the three years I’ve owned this car. It may have been running off stored pressure. That may not be possible as I was able to raise and lower the car. Ok so we will start from the first problem I was coming home and started getting a bad molten plastic smell no compressor noise but a hot bad smell. I thought that was odd and it was coming from my left headlight. I couldn’t figure out what was up until I got a message on my dash that Airmatic had a leak. I did some googling and realized that’s where my compressor is so I went home and parked it. Did some trouble shooting discovered the compressor wasn’t running. Checked the relay with a 9v battery it worked ordered a compressor. Ok now it gets fun. I unplug the relay and drive to work where I can use my lift. It rides like coil overs on a Honda it was pretty stiff. Ok get it on the lift pull the compressor and find the power connector was melted together. I break it apart but now I’m fixing the harness. Order the factory plug and pins from the dealer finally get that two days later solder in a length of new wire because my wires had melted near the plug. Get it all back together pretty and lower it down and...nothing works. WTF. I jump the relay compressor works but car won’t raise. ? I drive it home. Get a malfunction message and it’s riding a little soft. At home I realize the entire circuit is dead. ? I use a jack pull the wheel and fender liner no power at the compressor. Everything else looks good even the control plug has the correct voltage. But my big 40 amp fuse has no power I pull the fuse block expecting to have some molten wires but all is good so what’s going on?. This is where I’m about to torch the car when I find an old post in a UK forum. There’s a pre fuse box under the passenger floor. Sweet I pull back the carpet unscrew the cover and there it is a blown 40 amp maxi fuse. Change that reassemble and EVERYTHING WORKS!!! Redemption. I drive to the liquor store and get out and the compressor is running. And won’t stop. 😡. I pull the relay, getting pretty good at it at this point, and realize where this all started. My relay gets stuck when hot and causes all the other problems, burnt compressor, melted wires, blown fuse. I run down to the auto part store get a new relay plug it in boom no more problems. 👏🏻😁
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2002 CL500 to CL55 conversion
i havent actually pulled the cover to the prefuse box yet but all the surrounding wires were testing ok for me... running out of ideas, seems the relay gets power but the compressor does not. 40a fuse for the airmatic is OK, and i've tried swapping relays. found a bad bit of corrosion on the central gateway module under the left dashboard...cleaned that up and my "BRAKE INCREASED STOPPING DISTANCE" went away but the airmatic problem remains.
