And I’m not going to share pictures – the mechanical nature of this job is extremely easy. You’ve got 3 12mm bolts holding on a bracket that contains the air compressor that is covered by a shroud that clips onto the bracket – and there are 3 standard wire connections (2 from the compressor itself and 1 from the bracket) that connect to the bracket/pump – you basically disconnect those standard connectors on removal and reconnect them on install – couldn’t be easier. So this is very simple – and that’s the easy part. The hard part are the air suspension line connections. But if you follow some guidelines even those connections are easy. There is a large pressure relief line that has a spring clamp – you’ll remove that last. And there is an In and Out line that are threaded into the compressor – you’ll need a 12 mm wrench to loosen/tighten them.
Step 1 before you start you should use the system to put the car in its lowest suspension mode (I think maybe Dynamic or whatever mode causes the air suspension system to release as much pressure as possible from the system) and then disable the suspension through your infotainment settings inside the car. There are plenty of youtube videos on that topic – not hard to find – easy.
Step 2, The compressor is in the back of the vehicle tucked under and near the rear driver side bumper / rear driver side tire. So even though your compressor might not be working and you might have lost some air in your system for whatever reason – you still likely have pressure in those lines and in the system – so you don’t want to just go and disconnect things without considering the existing pressure in the system. And also, if you’re underneath the car and it loses pressure – the car will start to sag and what if you’re under it? So put a jack under the rear transaxle differential and pump it up just enough (not necessarily tires off the ground) to provide some support for when any air suspension existing pressure leaks out – and it would be smart to put some jack stands in support locations because even jacks fail or lose pressure themselves.
Step 3, disconnect the negative terminal of the battery. I think its a 10mm wrench to loosen the one that goes right on the lug – and take that entire ground assembly up and off the lug.
Step 4, disconnect the clips that hold on the compressor shroud under the car and remove the shroud.
Step 5, disconnect the 3 electrical connectors from the compressor.
Step 6, make sure you get a camera, video, tape – whatever you have to do to mark – and make sure you know where each line goes back on the pump when you go to reinstall it.
Step 7, get a 12mm wrench on either the in or out line and slowly and carefully start to loosen one of those fittings until you start to hear a little hissing sound like air is leaking out…and then STOP. Go grab a beer, mow the lawn, etc. come back to check every now and then until you don’t hear a hissing sound. Then repeat that step of slowly and carefully loosening that same fitting you were loosening the first time, and if you start to hear more hissing – repeat the step of pausing and waiting until you get to the point where you are free of any hissing – that means you’ve released the air pressure in the system and can now start to remove the other air line fitting and the larger spring clamped one in the middle (note on that one, just use a small pair of channel locks to release the spring pressure on the clamp and move the clamp upward on that same line till its entirely away from where it tightens down on the nipple of the fitting. Then try to get both hands in there to twist and pull at the same time and work it out – it might be tough to get it out but you will eventually work it out.
Step 8, loosen the 3 12mm bolts that hold on the bracket and remove the compressor from underneath the vehicle.
Step 9, I recommend not replacing with the OEM – since there is an issue with the original. In my searching, I decided to go with the Arnott replacement – you can get different flavors of this pump with or without the bracket – I decided to just get the basic Arnott replacement pump because the bracket I already had and the existing hardware was in tact and in good condition. You may want to decide to replace the entire bracket and pump…..that is a little more money but definitely makes re-install a little bit easier. But it’s pretty easy to spend a little less money and just take the old pump out of the existing bracket and put the new one in….saves about $100 or more to do it this way and it really isn’t much extra work. But you do want to make sure your existing bracket parts i.e. The springs and bolts etc. Are in good condition because if not you’re going to get vibration and louder unpleasant noises everytime the pump turns on/off.
Step 10, basically, everything on the install is reverse of removal. But a few notes on the install – make sure to put the right In/Out lines int he right places per step 6 above. You don’t want to mix those up. When you reconnect the lines you are supposed to use the new fittings that come with the new pump – so this is what you should do. But what you can do is take very thin marker that you can see on a dark air line and make a mark at the end of the threaded fitting (nut) from the in/out lines you removed so that when you go to push (or thread) back in with the new fittings – you know the line depth is inside the pump the same amount as what you had before.
Step 11 – The Relay – so that diagram posted by volvogod does not answer the mail on the relay. Where in the “F” is the “Fing“ relay – Volvo people are so selfish on the proprietary VIDA thing they can’t even go to the extent to put an “Fing” diagram under the cargo fuse box cover to show which fuse/relay goes to what. You have to actually go online or perhaps open your user’s manual (wherever that is) to go figure this out and even then – there is zero null, nill, no information on what the relays are and where they are – just the fuses.
Anyhow, if you find the 40 amp air suspension compressor fuse you can pull that fuse. Then start pulling the larger grey/black 4 pin relays (one at a time) from their posts. Each time you pull one, you can do an ohm read between one of the fuse pins and one of each of the relay terminal post pins from the relay you just pulled. If you don’t get a reading from pin 1 on the fuse you pulled and between one of the relay pins from the relay you pulled, move to fuse pin 2 and repeat For the same relay post terminal. If no ohm reading, move to the next relay post terminal pins and do the same thing until you get an ohm reading – this is how you know you’ve got the right relay / air suspension fuse combination. And when you pull a relay, if you look close on the plastic terminal that you pulled it from, there will be a plastic alpha/numeric engraving that says “DR*”. So the Air Suspension Compressor Relay terminal post will have a “DR2” engraved in the plastic that you will see when you pull the relay from the terminal (ok, I could have started with that – but now you know how to go about figuring this out for the other fuse boxes).
All that being said, the right thing to do would be to test the relay – if it is good don’t replace it. If it is bad – replace it. The only reason Volvo says to replace it with the pump is because it’s an easy cheap thing to replace and you might as well. But also, there is a chance the relay is working intermittently due to its electro/mechanical function. But honestly, if you apply 12 volts to the terminals (find a car battery and some wire or maybe one of those impact tool batteries) and you test the open and close on the other 2 terminals several times in a row and don’t get intermittent results…..that’s reasonable objective evidence that your relay is good to go. Could it still be bad – ya – but so could the one you just purchased brand new Right? So arguably, you should also test the new one too if you’re going to that route. Of course, another options is to just use the car itself to test it. In that case, if everything works – it just works – so you know you have a good relay. But if it doesn’t – now you’ve got to wonder – and it’s entirely possible it could be because of the relay. Anyhow, I recommend testing the relay and only replacing if it’s bad.
Step 12, once you’ve got everything in place and buttoned up – compressor connections in place – jack stands/jack removed – time to reconnect the ground battery terminal cable. Then get back in the driver seat and re-enable the suspension from the infotainment screen. Once everything stabilizes, try going to different suspension settings/modes and make sure the response is what you expect. You‘re done. Note, if you reconnect the battery cable and didn’t disable the suspension in step 1, it will likely just start pumping air into the system right off the bat – because it will start detecting the discrepancy as soon as it gets power. Also note, your problem this entire time may not have had anything to do with the compressor (or relay or fuse). You may have other issues with one of the front air struts or rear bladders or an air leak somewhere in the system. Over a long period of time, the air will eventually leak out – but over shorter periods of time (say a week to a month of letting a car sit in the garage without touching it) if you see sagging in the front or rear – you know you’ve got a leak somewhere – which could be why your compressor is bad because it is being overworked having to turn on/off more often than it normally other wise would with a nice buttoned up closed system with no leaks. But also, there is a known issue with the OEM pump for people in cold environments – and there are many posts on this. It is absolutely true that temperature may affect it – especially very cold temperatures. Don’t buy one of these cars with the air suspension if you will be driving in extreme cold environments. Opt for the regular suspension in that case.