Had a lot of trouble finding steps to do this, even initially finding where to get service documentation for Mercedes can be a challenge, let alone steps for a DIY operation for a car like this. Hopefully this is helpful to others going through the process. However, proceed at your own risk.

Assembly/Disassembly:

1. Remove lower liftgate trim (instructions attached)
2. Remove static/non-static spoiler (instructions attached)
   • Remove or add active (non-static) spoiler control unit (instructions attached)
3. Attach new spoiler using same instructions
4. Re-code the car

Re-coding:
You'll need a computer to connect to your car, as well as the DoIP device to bridge the connection. If you don't want to go down the can of worms of finding software, compatible DoIP device, etc., I highly recommend a @BenzNinja membership to help get you everything you need, equipment, software, etc.. (in fact, he can do this coding as part of the membership voucher if you join). Otherwise, if you have equipment and software:

1. Ensure your car is on a charger
2. Connect it to the system
3. Put your car in ignition 2
4. Using DTS Monaco, open the `DRVU_NG` module for your car
5. Next, unlock security access in ECU
   • Web search "DTS Monaco unlock security access in ECU" (Russian YouTube video w/English subs)
6. Apply the following settings:
   • [003] WingCtrl_Coding_String Write
     • Set `WingCtrl Parameter` to your new spoiler `Fester Spoiler` is fixed (static) spoiler
   • [006] MiKo_Coding_Parameter Write
     • Set `MiKo Rear Wing Logic` to new spoiler or `none`
     • Reorganize `MiKo Switch<1-8> VF Assignment` to add or remove the `Rear Wing (Heckspoiler)`
   • [007] SCM_Coding_Parameter_Write
     • Set `Rear Wing Logic` to your car or `none`
7. Disconnect in the software, unplug and turn off your car

With that, the error is gone and your speed is no longer limited to 100mph. The spoiler option is also added/removed from steering wheel knob (if you have it), center console button, and cluster display.

Great post! This type of stuff should honestly be a sub-section of the forums. I think you need to update some things for your ESP too though, have you checked if ESP is still working after doing this?

Crap, just checked it and you're right. The ESP button doesn't work. I'll have to look into that.

That's why I'm picky with sponsors, looks like you paid for a Benz-Ninja membership and even tagged him last month in this thread. What was his response? From your last reply it appears he completely ignored your tag and left your ESP broken. From looking at his site the membership fee looks like it's just so you can pay him to fix your car, but any other sponsor will do that without a membership fee. Personally I would have saved my money and just used another.

I don't think he ignored me. I'll give him the benefit of doubt on that one, he probably just didn't know much about the procedure is my guess.

Any can help occupy same

For coding instructions? This guy's steps are probably good except the ESP stuff, I might be able to find out that but need to check my resources. I want to say there is an ESP module you need to update but could be wrong.

Finally figured out how to fix my ESP, there's one final coding process:

Re-coding:

1. Open `ESP290_AMG` module for your car in DTS Monaco
2. Unlock security access in ECU on "Diagnostic Services" tab (same as with the other module)
3. Go to the "Variant Coding" tab and apply the following setting(s):
   • [032] Aerolimiter Coding Write
     1. Set `Aerolimiter Coding` to `off`
     2. If `Aerolimiter BackUp maximum velocity` has a value, set it to `0` (equivalent to unset)

Covered the rest in my last post. If the coding steps are above your head with your current knowledge, can always hire a sponsor from these forums to do the coding part for pretty cheap. They probably know how already, but wouldn't hurt to share a link to this thread incase they're new to this specific configuration change.

Hello all, I'm giving this a go likely with coding help from a local indie shop or rjautomotive. Forgive me if this info is located in one of the attachments, but what are the parts/part numbers for the active to fixed wing conversion? I have been searching on mbparts and no luck. Thanks

If you buy Genuine from Mercedes you're paying a lot, a lot of stuff relating to the wing itself is usually backordered or not available. And with any of the options you will also need to paint the spoiler support bracket to match your car, so consider that as well.

Spoiler Support Bracket:

• A29079302009999
• A1907920100
• A1907920200
• A1907920500
• A1907920600
• A1907931200

Wing (one of many options):

• A2907901000

Cheaper OEM option:

• Mercteil sells a kit: https://mercteil.com/amg-gt-static-r...retrofit-P5xv0

Total Cost: ~$4,500

Pro tip:

• Buy the support bracket directly from mercedes: A29079302009999
• Buy an "OEM Style" spoiler assembly w/wing of choice from AliExpress

Total Cost: ~$2,000

The support bracket (A29079302009999) included in the assembly from AliExpres you pick should match the exact design of the OEM support bracket, so look closely when buying. The problem is 9 times out of 10 their lower support bracket will screw on just fine, but won't align perfectly with your car lines on the bottom, if you care about that. That's why you probably want to buy that part from Mercedes. Then use the AliExpress wing/carbon fiber and the bolts/washers/etc from the lower support bracket it comes with.

wow… very detailed! Thank you. Correlating this info with the quote from the parts guy I worked with.

Mercteil is tempting. Although I’d need it shipped to the USA.

Do you have experience with them?