dgiturbo

After I parked and switched off, I heard a constant buzzing sound from the passenger side headlamp. It was the Airmatic pump running itself to oblivion. Ride height and road feel was fine, and the vehicle still raised and lowered on demand.
Fault was the green Tyco relay in the engine compartment relay box. (Box is on the front passenger side, relay is 3rd from left)
Replaced the relay with an updated Hella unit from the dealer, ($40) and problem solved. Hope this helps others.
FYI in checking around, seems like the factory Tyco relays are "not as strong" as the Hella units, so would advise replacing before you have an issue.

Moto One

Thanks

Mark

dgiturbo

Note to all with Airmatic air suspension:
Switch the Tyco relay ASAP for the Hella unit.
The relay price will pale in comparison to the Airmatic Pump price. These pumps can run from $380-550 for just parts depending on where you find it.
Be proactive on this one!!

dgiturbo

The Mercedes part number should be 0025427619.
It is a green relay 3rd from the left in the front engine compartment fuse box. Make sure the replacement is a Hella unit. The ones at parts stores may not be correct as this relay is what I call a double throw, single pull. This one looks like it sends current to BOTH 87a and 87 pins, not one or the other.
Hope this helps.

le_barn

Hi,

I have just had this exact same problem. The compressor wouldnt stop working even after the car was off, locked etc. After some helpful advice from MBWorld i took the 40A fuse out to save a full meltdown of the pump and a dead battery in the morning..

The missus used the car during the next day with the fuse out, the only effect being that the front of the car sank down a bit on the air springs. Anyway, i popped into the stealership and bought replacement relays, apparently the Hella ones are now standard replacement parts (complete with MB logo on) so i got two as there are two of the nasty green tyco relays in the fuse box.

I replaced the relays and all is ok now. Im just recovering from an air spring replacement and couldnt handle another repair.. just thinking about the bill from that brings me out in a cold sweat.

Anyway, i posted a few pics as a guide to anyone with a W164 having a similar prob or simply wanting to replace the nasty green tyco relays. Hope it helps.

PS Part nos. as follows:

Old Part - Tyco 002 542 2319
New Part - Hella 002 542 7619

newguy2008

Hi, any idea what the 1st relay on the left is for?

I have a Tycos in the 1st relay spot and a Hella relay in the 3rd spot. Can they be swaped in positions for each other?

I moved the Tycos relay to the 3rd spot where the Hella relay was and moved the Tycos to the 3rd spot to see if anything changed. But still nothing, my compressor cannot be heard with the car running. The relays look like the same type of relays. What are the chances that both Relays are bad at the same time?

Roland Waters

Many thanks for this info......while here in the UK we have our steering wheels on the correct side, the info enabled me to find the nasty green offender to pull to stop the air pump going until it died of exhaustion. Once again, many thanks to our cousins in the old colony now of course, the USA.

Peace and love.

Roland Waters

Help! Same issues with suspension air pump running when all turned off - new genuine updated relay fitted but - the car stops itself 3-5 seconds after starting! Put old relay back in which is burnt and car starts and runs!? Is there a known earth issue? Anyone, please?

Roland Waters

Fitted new relay from Merc and now car stops after 3-5 seconds! Put old relay back in and car starts and runs but no suspension pump working!?

Maj. Dundee

Roland, please UPDATE YOUR PROFILE in USER CP to include year and whether the 320 is gas or diesel and where you live.

Maj. Dundee

What was relay # and which fuse box was it in?

sciroccor

!!

HoratioB

OMG OMG OMG!!!!!
le_barn, Thank you so much for this post from 2013!!!! I have a 2012 GL450. I already paid to have the rear air struts swapped out along with the compressor. 3 years later I had the front air struts swapped out and the distributor and all seemed well until.... the compressor was running constantly then all of a sudden it wouldn't even kick in anymore and the front just stayed down. In my great frustration I was getting ready to throw even more money at it. But this first picture in your post with someone swapping out that big 40amp fuse made me realise that the compressor has a relay and (to my own amazment) a FUSE. I tried and sure as heaven the compressor lifted the care right back up. You saved me A LOT of money as I was just gonna go to the dealership an ask them to put in all brand new parts. Thanks again!!!

jam2reggae

What is the part number for the orange fuse you are holding in your hand in the picture? I need to replace 2. I tried to remove them but the casing got broken.

Thanks
Lanny