Retrofit Air Suspension to 2016 4M Q7 - Let the journey begin

[davus]

Hi All,

Coming to you from Melbourne, Australia here. So keep that I'm mind as you read this post.:) Also as but of a heads up, it might be a little wordy.

A little background before we kick off. I've recently upgraded from a 4L Q7, to a 4M. My 4L was a 2008 model, and had every option available at the time of purchase. One of which was adaptive air suspension, which is the focus of this thread.

As I was shopping around for my new car, I came to the realization that in Australia, the 4M Q7 does NOT come with air suspension. Only the SQ7 - The price of which (even second hand) was not viable for my budget.

I tow a 3.4 ton boat, with roughly a 300kg tow ball downforce. The air suspension in my 4L was absolutely brilliant at levelling the car back up when loaded, and was a beautiful ride (and tow car). Fast forward to the 4M, and the reality is the strain it puts on the standard steel suspension is just too much. The rear of the car sags significantly, which impacts steering / handing etc. So, I've made the decision that I'll be retro fitting the Adaptive Air Suspension.

I'm comfortable in my ability to do all this work, but some parts will need to more investigation and research than others. No doubt.

I see there being three main areas I'm going to need to tackle.

1) The Mechanical
I'm my mind, this is the easy bit. Turning spanners is pretty easy. I've used various resources the understand the majority of the parts I need, and have started the process of purchasing them.
Even thought not exhaustive, this is the backbone of what I've found so far.

Part Description Audi Part number Possible Superseeded part numbers
FL shock 4M0*616*039*AC 4M0*616*039*AD, 4M0 616 039 AE
FR Shock 4M0*616*039*AC 4M0*616*039*AD, 4M0 616 039 AE
RR Shock 4M0 616 031 AG
RR Airbag 4M0 616 002 AB 4M0 616 002 G
RL Shock 4M0 616 031 AG
RL Airbag 4M0 616 001 AB 4M0 616 002 G
RR Level Sensor 4M0*941*309*G 4M0*941*310*G, 4M0 941 309 H
RL Level Sensor 4M0*941*309*G 4M0*941*310*G, 4M0 941 309 H
FR Level Sensor 4M0*941*285*C 4M0*941*286*C
FL Level Sensor 4M0*941*285*C 4M0*941*286*C
Valve Block 4M0 616 013 A
Compressor Assembly 4M0 616 005 F
Compressor Cover 4M0*616*105*E

I'm still trying to figure a couple of things out to do with air lines, and how the pressure accumulator fits into the equation.

2) The Electrical
This is the bit I'm going to struggle with the most. The car does not come prewired with any of the required cabling, so I'm going to have to either build my own wiring, or try to understand if there is a standlone loom I can buy - not sure about this yet.

I have all the relevant wiring diagrams and manuals that will help, but haven't started getting into this bit yet.

3) The Coding
This bit will take work, but again I think is fairly straight forward. I have RossTech VCDS, and am comfortable in making the actual changes, i just need to do the homework on all the bits and pieces the needs to be modified.

I'm going to attempt to keep a photo diary of the upgrade as I progress, and will post here as i go for all to see.

If anyone has any insights, experience or has undertaken this retrofit before, I'd love to hear from you. There are still a lot of the gaps in the knowledge I have, particularly around the electrical and wiring.

Also, ask a bit of an ask to the group. If you have a 4M with Air Suspension, and happen to have any photos at all of the undercarriage or suspension components, i would really appreciate you sending them to me, or posting them here. I don't have a lot of photographs to reference, and i think those photos would be super helpful.

Thanks!

Dave

[SQ57]

G'day mate! Let's put another shrimp on the Barbie!!!
"Let's not"..
This reminds of my ol' mate Peter Graham, he would just go against anybody(or anything-including a bus), and somehow make it thru...

Seems like an tremendous project, hope to see it thru.

Cheers, mate
Happy new year too!

Sent from my SM-S908U using Tapatalk

[davus]

G'day mate! Let's put another shrimp on the Barbie!!!
"Let's not"..
This reminds of my ol' mate Peter Graham, he would just go against anybody(or anything-including a bus), and somehow make it thru...

Seems like an tremendous project, hope to see it thru.

Cheers, mate
Happy new year too!

Sent from my SM-S908U using Tapatalk

Thanks man! - Its no doubt going to be a decent undertaking. But with three kids, a mortgage, a wife, and a job...........It's almost like I've got nothing better to do!

[davus]

Hi All,

So, first question.

As i try to determine all the parts i need, I've arrived at the homework section on level sensors. Now, looking underneath my car, i already have level sensors. I understand it has to do with the headlights.

The bit thats puzzling me is, they're only on the left hand side of the vehicle (driver's side in my case).

My question is, are any of the Q7 owners with Air suspension able to confirm for me whether they have sensors on only the left side of the vehicle, or if there are sensors on all four corners?

Thankyou!

Dave

[brianlbairos]

Just a thought but since you want the air suspension mainly for towing..... does any company make a helper air spring setup... like you would install on a pick up truck and you could manually inflate or deflate the bags if you were towing? may be a much cheaper solution if available.

[davus]

Just a thought but since you want the air suspension mainly for towing..... does any company make a helper air spring setup... like you would install on a pick up truck and you could manually inflate or deflate the bags if you were towing? may be a much cheaper solution if available.

Thanks Brian. I did have a look into that, however i wasnt a fan of the solutions they had to offer. The main company in Australia that provides "helper" airbags is called "Air bag man"........to their own admission with the amount of downforce im looking at, even their high pressure solution would only lift the car about 50% of the way back up.

Plus - I have a bit of a soft spot for OEM if possible :)

Dave

[brianlbairos]

Thanks Brian. I did have a look into that, however i wasnt a fan of the solutions they had to offer. The main company in Australia that provides "helper" airbags is called "Air bag man"........to their own admission with the amount of downforce im looking at, even their high pressure solution would only lift the car about 50% of the way back up.

Plus - I have a bit of a soft spot for OEM if possible :)

Dave

Understandable and great to know.... I will be pulling a camper with my Q7 so i'm eager to see how much of pain it will be, keep us updated on how the process goes! Good luck

[jbain2]

I’m actually looking to do this in my 4L Q7 which doesn’t have factory air ride. I went the aftermarket route. But I’m going to follow this thread to see how you get along.


Sent from my iPhone using Audizine

[davus]

Hi All,

So - A generic question about the wiring stage of this project.*

A friend pointed me in the direction of a website called "Alldata". He pays a (pretty expensive) monthly cost for his array of jeeps. He showed me the "Interactive" wiring diagrams, and i have to say it was extremely impressive. Has anyone seen this?. You basically highlight a wire from the diagram, and it shows you interactively where that wire goes, all its connection points etc. It saves having to trace it back through each different page of a wiring diagram, and allows you to very easily trace an individual wire, and precisely where is runs and what it plugs into.*

In doing a little homework, it looks like this is something Bosch have put together (I've subsequently found other websites offering very similar products). Unfortunately they don't seem to provide anything on the Audi front.

The wiring component of this project is what daunts me the most. Its going to take the longest, and will be the most complicated.*

My question is, does anyone know of anything similar for the Audis? This interactive wiring diagram would be the answer to alot of my concerns I think. Im happy to pay a subscription or similar.*

Thanks!

[davus]

Hi All,
Im continuing to move through the project at a slightly slower pace than i was hoping, mainly because im trying to gather a full understanding of how the system works as i go.*

My next question is about the valve block. Is anyone here able to tell me the pinouts of 10 pin connector on the valve block itself (part number 4M0616013A)? I'm not talking about the wiring diagram (I have that), but the actual pinouts (positive / negative / etc). I'm wanting to try and manually activate the valves in the valve block*

Additionally, is anyone able to provide me with the same pinout data for the "Control Unit" . Its also mounted on the air suspension compressor assembly itself (part number*4M0907778). There are three connectors on it, each 2 pin.*

Attached are two photos of the parts im looking for pinouts for*






Thankyou!

Dave

[ucsbwsr]

Hey Dave,

Nice project. I am planning to do the same at some point on my wife's Q7 as the adjustability, performance, and ride quality of air suspension are very valuable to us. My personal vehicles are BMWs but I love OEM retrofits and have some experience doing projects like this, just not specifically with air suspension and not with an Audi platform. I have done general research on the project but haven't really dove into the details yet but trying to help you will also help educate me for my air retrofit. Hopefully we can make some progress together.

I have the full dealer-spec service manual, I'm assuming that's what you have too but if not let me know and I can send a DL link for it.

I took a look to see what I could find regarding your pin-out question for the valve block and control module. The Audi wiring diagrams are a bit different from the BMW ones and this link from RossTech was helpful in understanding them.

RossTech How to read wiring diagrams: https://forums.ross-tech.com/index.php?threads/1875/

This guide explains that the connectors in the wiring diagrams should be labeled like this T10/2. Meaning the wire being referenced is #2 in a 10-pin connector and when there are multiple 10-pin connectors they are listed as T10a, T10b, T10d, and so on. With the control module only having 2-pin connectors you can see it listed as "T2aq" and "T2ar" the 3rd connector isn't listed but presumably it is "T2ap" or "T2as" The pins are designated "T2aq/1" as the guide suggests it would be but rather there is a "v1" and "v2" which I can only assume are the pin locations in the connector. So just keep in mind this is an assumption on my end.


Regarding the control module (4M0907778) which is referred to as "J1135" we can see 4 of the total 6 connections listed with wire details.
"X1" connector is power into the unit: T2aq-v1 which is a Red w/Blue =Power. T2aq-v2 is ground.
"X2" connector is power and ground sent to "V66" which is the air compressor. This isn't clearly shown in the wiring diagram but utilizing Google images and process of elimination it becomes clear.
"X3" connector received inputs from the Drivetrain control module to activate the compressor module and therefore compressor. Not sure which one does what but with power into the module and compressor hooked up you should be able to use a 12v test lead and find out.

Here is the wiring diagram I referenced above


Here we can see "X2" is directly connected to compressor which means "X1" is power/ground in.



Regarding the valve block (4M0616013A) which is "NX7" in the diagram, things are a little less clear but we can draw some conclusions. First, with the assumption "V_" refers to pin location all pins are accounted for except for #8. Pin 7, 9, 10 connect the G291 pressure sensor to the J775 Drivetrain control module. G291 is clearly listed as part of NX7 so I assume it's a small switch/senor inside that receives input from the vertical-height level sensors located on the suspension control arms which read how high or low the vehicle is, this is then sent to G291 and then passed onto J775.

To be honest I don't really know what's going on with pins V1-V6. We can see N148, N149, N150, and N151 are the output valves for FR, FL, RR, and RL struts but it isn't clear on which pin is associated with which strut. N311 is the accumulator valve which is likely activated by pin V2 or V3, again not sure. I would assume the actuator valve would need to be activated and at the same time you would need to select one of the valves depending on what strut is to be filled. Looking carefully you will notice there are 6 pins but only 4 strut valves and 1 actuator valve so there is a pin that is shown in the diagram but unaccounted for, maybe a ground?

This is all I got for know, hope it helps,
Evan

Here is the diagram for the NX7 Valve Block:


Although the diagram only accounts for 9 pins the connector does appear to have all 10 used

[davus]

Hi Mate,

Thanks for your detailed reply Very informative.

I've now collected all the parts i need, along with all the relevant and correct wire trace colors. All i need to do now is find the time to start physically getting it all installed.

The mechanical parts will be very straight forward (Shockers/ Compressor unit / etc). The challenges will be in building the wiring loom, and the routing of the air lines throughout the underside of the car.

I have a bunch of documentation, and have downloaded a fair bit of info from Erwin - however if you have a workshop manual in electronic form, and be really appreciative of that.

Thanks!

Dave

[davus]

I was sure i replied to this thread, but it appears maybe i didnt hit the post button.

Im now at the point where I only have two or three small bits to get before i have all the hardware. Once ive got everything ill move onto the next bit. These are the requirements i still have in front of me.

1) Carry out the actual mechanical swapping of parts. This is straight forward, and i dont envisage any issue here.
2) Get all the wiring done. Ive struggled to find a factory wiring loom to buy, so im going to be building my own. Once built, i need to hook it all and make sure it works. Im sure ill have a couple of fixes and tweaks with this bit.
3) Sort out the programming side of things. At the moment this is the bit that is giving me the most concern. A couple of conversations ive had here seem to indicate the rather than being dataset driven, the coding for the Air Suspension is SWaP (Software as a Product), which is apparently much more difficult to sort out (I wont be doing the coding bit myself, thats outside my capabilities)

So, I have a couple of asks for the group, and id be super duper appreciative if someone might be able to help.

1) Does anyone with expert level coding capabilites be able to provide any commentary on the programming side of things here? I'd hate to get everything installed, only to figure out i cant program it.
2) Im still keen to try and get as many photos of other Q7's with Air Suspension. Id be really appreciative if anyone could share photos of their car. The areas im looking for photos of are: Shock / Strut area, Compressor area, Any photos showing air pipe routing (entry / eixit points into the car).

Again - Thanks in advance to anyone that can lend a hand here, or provide any information. Much appreciated.

Dave

[davus]

Hey Dave,

Nice project. I am planning to do the same at some point on my wife's Q7 as the adjustability, performance, and ride quality of air suspension are very valuable to us. My personal vehicles are BMWs but I love OEM retrofits and have some experience doing projects like this, just not specifically with air suspension and not with an Audi platform. I have done general research on the project but haven't really dove into the details yet but trying to help you will also help educate me for my air retrofit. Hopefully we can make some progress together.

I have the full dealer-spec service manual, I'm assuming that's what you have too but if not let me know and I can send a DL link for it.

I took a look to see what I could find regarding your pin-out question for the valve block and control module. The Audi wiring diagrams are a bit different from the BMW ones and this link from RossTech was helpful in understanding them.

RossTech How to read wiring diagrams: https://forums.ross-tech.com/index.php?threads/1875/

This guide explains that the connectors in the wiring diagrams should be labeled like this T10/2. Meaning the wire being referenced is #2 in a 10-pin connector and when there are multiple 10-pin connectors they are listed as T10a, T10b, T10d, and so on. With the control module only having 2-pin connectors you can see it listed as "T2aq" and "T2ar" the 3rd connector isn't listed but presumably it is "T2ap" or "T2as" The pins are designated "T2aq/1" as the guide suggests it would be but rather there is a "v1" and "v2" which I can only assume are the pin locations in the connector. So just keep in mind this is an assumption on my end.


Regarding the control module (4M0907778) which is referred to as "J1135" we can see 4 of the total 6 connections listed with wire details.
"X1" connector is power into the unit: T2aq-v1 which is a Red w/Blue =Power. T2aq-v2 is ground.
"X2" connector is power and ground sent to "V66" which is the air compressor. This isn't clearly shown in the wiring diagram but utilizing Google images and process of elimination it becomes clear.
"X3" connector received inputs from the Drivetrain control module to activate the compressor module and therefore compressor. Not sure which one does what but with power into the module and compressor hooked up you should be able to use a 12v test lead and find out.

Here is the wiring diagram I referenced above


Here we can see "X2" is directly connected to compressor which means "X1" is power/ground in.



Regarding the valve block (4M0616013A) which is "NX7" in the diagram, things are a little less clear but we can draw some conclusions. First, with the assumption "V_" refers to pin location all pins are accounted for except for #8. Pin 7, 9, 10 connect the G291 pressure sensor to the J775 Drivetrain control module. G291 is clearly listed as part of NX7 so I assume it's a small switch/senor inside that receives input from the vertical-height level sensors located on the suspension control arms which read how high or low the vehicle is, this is then sent to G291 and then passed onto J775.

To be honest I don't really know what's going on with pins V1-V6. We can see N148, N149, N150, and N151 are the output valves for FR, FL, RR, and RL struts but it isn't clear on which pin is associated with which strut. N311 is the accumulator valve which is likely activated by pin V2 or V3, again not sure. I would assume the actuator valve would need to be activated and at the same time you would need to select one of the valves depending on what strut is to be filled. Looking carefully you will notice there are 6 pins but only 4 strut valves and 1 actuator valve so there is a pin that is shown in the diagram but unaccounted for, maybe a ground?

This is all I got for know, hope it helps,
Evan

Here is the diagram for the NX7 Valve Block:


Although the diagram only accounts for 9 pins the connector does appear to have all 10 used

Hi Mate - Have you made any progress on yours? I have a pretty solid understanding of what needs doing now, and about to start putting together the wiring loom. Ive got hundreds and hundreds of reference photos ive gathered. I also found a guy over int he Ukraine selling a complete air suspension kit. I didnt want to pay the thousands and thousands he wanted for it, but i did pay him $100 USD to send me masses of photos and videos (connectors, plugs / part numbers etc), which i used to gather all the relevant plugs etc. I have chosen with plugs and pins to source aftermarket as Audi prices on simple plugs / pins and connectors are just highway robbery.

I need to get hold of a few more level sensors, and then ill start building the wiring loom. I still need to sort out programming, which im starting to think will be a real challenge.

Dave

[jbain2]

I was sure i replied to this thread, but it appears maybe i didnt hit the post button.

Im now at the point where I only have two or three small bits to get before i have all the hardware. Once ive got everything ill move onto the next bit. These are the requirements i still have in front of me.

1) Carry out the actual mechanical swapping of parts. This is straight forward, and i dont envisage any issue here.
2) Get all the wiring done. Ive struggled to find a factory wiring loom to buy, so im going to be building my own. Once built, i need to hook it all and make sure it works. Im sure ill have a couple of fixes and tweaks with this bit.
3) Sort out the programming side of things. At the moment this is the bit that is giving me the most concern. A couple of conversations ive had here seem to indicate the rather than being dataset driven, the coding for the Air Suspension is SWaP (Software as a Product), which is apparently much more difficult to sort out (I wont be doing the coding bit myself, thats outside my capabilities)

So, I have a couple of asks for the group, and id be super duper appreciative if someone might be able to help.

1) Does anyone with expert level coding capabilites be able to provide any commentary on the programming side of things here? I'd hate to get everything installed, only to figure out i cant program it.
2) Im still keen to try and get as many photos of other Q7's with Air Suspension. Id be really appreciative if anyone could share photos of their car. The areas im looking for photos of are: Shock / Strut area, Compressor area, Any photos showing air pipe routing (entry / eixit points into the car).

Again - Thanks in advance to anyone that can lend a hand here, or provide any information. Much appreciated.

Dave

It seems like the biggest barrier is going to be the coding/software. Can I ask why you felt comfortable buying all hardware before you sorted out the feasibility of the coding? I have all of the components for an aftermarket air ride install with airlift components. I’ve had a couple maintenance things creep up shiv I had to tackle first before installing the air ride


Sent from my iPhone using Audizine

[davus]

Hi mate. Fair question.
I’ve used the same person to do quite a bit of coding on my car, and in my initial conversations with him, the coding never came up as a concern.
It’s only been in our recent conversations that things have started coming to light.
I don’t hold that against them though. They’re confident it can be done….and this seems to be a retrofit I haven’t found anyone else undertaking that I can see.

[ucsbwsr]

Hi Mate - Have you made any progress on yours? I have a pretty solid understanding of what needs doing now, and about to start putting together the wiring loom. Ive got hundreds and hundreds of reference photos ive gathered. I also found a guy over int he Ukraine selling a complete air suspension kit. I didnt want to pay the thousands and thousands he wanted for it, but i did pay him $100 USD to send me masses of photos and videos (connectors, plugs / part numbers etc), which i used to gather all the relevant plugs etc. I have chosen with plugs and pins to source aftermarket as Audi prices on simple plugs / pins and connectors are just highway robbery.

I need to get hold of a few more level sensors, and then ill start building the wiring loom. I still need to sort out programming, which im starting to think will be a real challenge.

Dave

Hi Dave, No update on my end as I am far from tackling this Q7 project. I have a garage remodel to finish, then an BMW E39 Touring build, and some projects on my X5 which will happen first. As for the coding, when I was posting some speculative air suspension retrofit questions/comments in some Q7 Facebook groups there was a 4L owner that chimed in and said he had previously completed the retrofit, I can't seem to find the post where this comment was made but pinging the Q7 FB groups to see if this guy surfaces might be useful. Technically I don't know how the 4L and 4M air suspension systems compare but I would assume there is a fair amount of similarity.

I have also seen some posts on Facebook from people who specialize in OEM retrofits for the Q7, they commonly share projects where they added adaptive cruise, nigh vision, etc. and seem to have a handle on more advanced coding, I assume with VCDS. Connecting with them might be useful for guidance if they aren't able to assist with coding themselves.

Sorry, I'm not more helpful!
Evan

[mistaleung]

Hi Dave. Did you finish your air suspension project?
I have found a coding guy to do the job on my Q5 B9 and I am starting to source all the parts and now stuck with the harness.
Would be great if you have any insight to share with :)