Mercedes-Benz 722.9 ISM Intelligent Servo Module Repair and Cloning Service

Mercedes stuck in park? Will not shift? Will not crank? This is the part that failed.

Your car does not need a tow truck and it does not need a dealer. Pull one module off the transmission, ship it to us, and we send back a new unit carrying your own VIN. Bolt it on and drive. You can do the removal in your driveway in about an hour.

How this usually starts

It almost never fails all at once. First a message shows up on the dash while you are driving, something like "Drive to workshop without changing gear" or "Service Required Do Not Shift Gears." The car still drives. Most people finish the errand and figure they will deal with it later.

That message is the warning shot. It is the transmission telling you that once you shut it off, it may not be able to select a gear again.

The next morning the stalk does nothing. No click, no response, no gear change. The indicator in the cluster is blank or stuck on P. Turn the key and it may not even crank, because a Mercedes will not engage the starter until something confirms the transmission is actually in park. Nothing is confirming it, because the part that reports position is dead.

The car is now locked in place in your driveway. That is the Intelligent Servo Module, component A80, and this page is about the two ways out.

Does this sound like your car?

This shows up on the E350, E550, C300, C350, ML350, ML550, GL450, GL550, S550, CL550, CLS550, R350, SL550, GLK350 and G550 among others. If it has the 722.9 seven speed and the stalk shifter on the column, it has an ISM and the ISM can fail.

Fault codes that point here: 1994 (A80 cannot reach the specified target position), 1904 (internal mechanism in A80 not in the correct position), 1922 (system shut down due to an internal fault), 1974 (selector lever position implausible due to a fault in A80), 5399 (ESP CAN signal, gear selected, implausible), C103 ETC (no CAN message received from A80). Xentry will often just say no communication with A80.

From here you have two choices

How it works

1. You remove the ISM. It is bolted to the transmission and reached from underneath. On most models it is a splash shield, one electrical connector, and three bolts. Jack stands and basic hand tools, about an hour. Free step by step removal guides are on youcanic.com. If you would rather not crawl under it, any independent shop can pull it in well under an hour of labor, and they need no Mercedes specific tooling to do it.

2. You ship it to us. Wrap the connector, drop the packing slip in the box, and send it to our office in Baltimore, Maryland.

3. We read your data and clone it onto a new unit. This is the whole trick. Your original ISM holds your VIN, your DAS pairing and your adaptation data. We pull that data off it and write it onto a brand new module. What comes back to you is new hardware that your car believes is the module it has always had.

4. It ships back in 3 to 5 days. Tested before it leaves.

5. You bolt it on and it is over. Three bolts, one connector, splash shield back up. Turn the key and the car shifts. No dealer appointment, no coding software, no scan tool, no VSP paperwork, no tow bill.

Your original module stays with us. You are getting new hardware in exchange, not your old unit patched up.

If your old module is too far gone to read

Occasionally water intrusion or a burned trace takes the memory with it and there is nothing left to clone. You are still not stuck.

We ship you a new unit along with a programming dongle. You install the new ISM on the car first, then plug the dongle into the OBD port. All you need on your end is an Android phone. We connect remotely and program the module to your car ourselves, while it sits in your driveway.

You do not need a laptop, a scan tool, diagnostic software, or a Mercedes account. You need the phone and a few minutes.

Why the dealer route runs close to $2,000

Your car cannot roll. Stuck in park means the output shaft is locked. It cannot be driven and it cannot be pushed onto a wheel lift. It takes a flatbed with a winch and skates or go-jacks. That is $150 to $350 before anyone has touched the car.

You are not allowed to buy the part. The ISM is a Mercedes Theft Relevant Part. It cannot be sold to you, and it cannot be sold to your independent shop either. Ordering one requires a NASTF registered Vehicle Security Professional to submit a signed D-1 form, your title or registration, government photo ID for both you and the VSP, and a repair order carrying your VIN. That paperwork wall is the real reason people end up at the dealer. It is not the price of the part, it is that the dealer is the only door.

Then it has to be coded. A dealer unit arrives blank. It has to be SCN coded online through Xentry, run through initial startup, and the selector lever has to be adapted. The aluminum mounting bolts are single use and cannot be reused.

What owners actually report paying: $1,000 on a 2014 W212. $1,520 on a 2011 E550 4MATIC. UK owners report over £1,000 for the same job. Add the flatbed and most people land between $1,150 and $2,000 by the time the car is back in their driveway.

Cloning your data onto a new unit skips every one of those steps. Your VIN is already on it before it ships.

Part numbers and fitment

Also stamped as 0002701852, 0002701752, 0002704452.

Chassis codes: roughly 2006 through 2018. C-Class W204 and W205. E-Class W211 late, W212, W207. CLS W219 and C218. CLK W209. S-Class W221. CL C216. ML W164 and W166. GL X164. GLS X166. GLE C292. GLK X204. R-Class W251. G-Class W463. SL R230. SLK R171 and R172. Gas, diesel, 4MATIC and AMG all use the same module.

Check the label on top of your module before you order. The number is printed on the plastic housing next to the connector. If your number is not listed, send us a photo and we will tell you straight.

Why these fail

Worn brushes and a burned commutator in the servo motor, which runs every single time you touch the stalk. Cracked solder joints on the board from years of heat cycling on top of a hot transmission. A shredded drive belt or stripped screw shaft, so the motor spins and the lever never moves, which is fault 1994 in one sentence. Position sensor drift, where the module still moves the lever but can no longer confirm where it landed. Or corroded pins and water intrusion, common on the ML and GL where the module sits right in the splash path.

Every one of those is worn out hardware. That is why the answer is a new unit carrying your data, not a patch on a module that has already given you everything it had.

Questions we get

My Mercedes will not come out of park. Is it always the ISM?
Not always, but it is the first place to look. Rule out a weak battery and a blown fuse first. If voltage is good and the stalk still does nothing, it is the ISM. Always read the codes with a full system scanner like the YOUCANIC UCAN-II pro. 

My Mercedes will not start and will not crank. Related?
Usually yes, and it is one failure causing both symptoms. The starter stays locked out until the ISM confirms park or neutral.

What does "Drive to workshop without changing gear" actually mean?
The ISM has logged a fault and is telling you that once you stop or shut the car off, it may not be able to select a gear again. Do not ignore it. That message is your window to get the car somewhere convenient before it locks in park.

Do I get my own module back?
No. You get new hardware carrying your data. Your original stays with us.

Will I need the dealer or a scan tool afterward?
No. The unit ships with your VIN and your adaptation data already on it. Bolt it on and drive. The only exception is if your old module is too damaged to read, and in that case we handle the programming remotely with the dongle and your Android phone.

Is it the ISM or the conductor plate?
The conductor plate causes shifting faults while driving, harsh engagement and gear specific problems. The ISM causes the car to not select a gear at all. If you cannot leave park and the stalk does nothing, that is the ISM.

Can I just buy a new one myself?
Not easily. Mercedes will not sell an ISM to you or to your independent shop through normal parts channels, and a unit bought elsewhere still arrives blank. See the Theft Relevant Part section above.

Can my local shop do the removal?
Yes, and they need no Mercedes specific tooling. It is three bolts and a connector. The specialized work happens on our bench.

Do I send my key?
No. Just the module. Never mail your key.

If you want a duplicate key done, that is another service and requires that you send the ignition switch to us. 

How long does it take?
3 to 5 days on our end, plus transit each way.

Start it now

Add to cart and we will email your packing slip. Pull the module this weekend, ship it Monday, and you are driving again instead of paying two thousand dollars and a tow truck.

Not sure it is your problem? Send us a photo of your module label and whatever fault codes you have before you order. We will tell you honestly whether this is it, even if the answer costs us the sale.

Module Medics. Mercedes module cloning and remote programming, Baltimore, Maryland.