MK7 R rear kessy door handles retrofits

I am writing this post as a guidance for those who would like to retrofit rear kessy door handles to MK7 Golf platform.

As an extra information, it has been done on mk7.5 golf, but mk7.5 already has the new kessy module which has 40 pin connector (3Q0-959-435-G).
In this case you have only to buy the handles (same as front ones) every handle has 4 wires, one ground and the other three goes directly to the kessy module, with little coding adjustment you can make it work

Most Mk7 cars has the old 32 pin connector kessy module (5Q0 959 435 B), so there is no extra space for the new handle wires.

After comparing the wiring diagram from mk7 to mk7.5 , I swapped my old kessy with the new one, where i have also to add extra interior antenna.

Also this required VCP tool to do parametrization for the new module.

The conclusion is , it can be done
Just wanted to share this and for anyone planning to do it i am here to help or even give guidance and wires location map (I don’t know how you post pictures here)

But i am really enjoying my rear door kessy handles :-).

good job. if only I had rear doors

Qassem,

I'm very interested in how you went about retrofitting the 40 pin connector (3Q0-959-435-G) and how to load the new dataset onto the module using VCP. I've run into the same issue on my mk7 golf R.

Thanks!

I'm looking for some assistance to understand the complexities and the dataset/coding needs required to changing out the 32-pin KESSY module (3Q0959435C) from my 2017 MK7 Golf R to the MK7.5 Golf R KESSY module (3Q0959435L). I've attempted this retrofit with a local dealer and with a local tuner (skilled with ODIS) with both unable to get past ODIS messages stating that the module is not intended for chassis and was not able to be adapted. Neither had any success or knowledge of anyway around the message. My next step is to go back to the dealer with the 3Q0959435G and see if we can get that one to work. Otherwise, the master tech at my local dealer said that because of the way ODIS has been centralized at VW corporate, he can't get past the message from ODIS identifying the 435L module not associated with the build certificate. Any incite or suggestions would be appreciated. Thanks! I understand that this modification may no longer be possible due to ODIS hurdles.

I think if you pull the ECU and Instrument Cluster fuse (Fuse 17 of the engine and cabin panel) while ODIS is looking for the VIN it will (of course) not be able to find it and then ask you to manually enter it. You then enter a VIN for a car that came with the module you want to parameterize. Once the parameters/dataset have been loaded I assume you could close that session, probably want to cycle ignition, then go back in and do whatever else needs to be done.

@Cuzoe that's not a bad idea actually. Have you ever tried doing anything of that nature? Curious to see the expression on the MM face when I suggest that, lol. I do have the VIN of the car the KESSY module came from. hmmm.

Cuzoe said:

I think if you pull the ECU and Instrument Cluster fuse (Fuse 17 of the engine and cabin panel) while ODIS is looking for the VIN it will (of course) not be able to find it and then ask you to manually enter it. You then enter a VIN for a car that came with the module you want to parameterize.

Click to expand...

I don't know whether that actually works, but make damn sure you've saved a complete Auto-Scan before attempting this because there's good chance doing this will zero out your ABS coding.

-Uwe-

On more than one occasion during remote sessions for my retrofits the folks doing the work have asked me to pull those two fuses. I eventually asked why and they told me, in a round-about way, the reason was so ODIS wouldn't limit them based on my actual VIN. I didn't dig into it much since whatever they were doing always got my new stuff working . I later read somewhere this would let you enter the VIN manually.

As far as trying it on my own... I have not. I have never used ODIS on-line for anything so my VIN never mattered too much. I've only used ODIS (off line) to flash software/datasets that I had acquired elsewhere, nothing pulled down from VW servers myself. Try at your own risk, of course. And yes, ALWAYS have a recent scan. I tend to run an auto-scan before I do most anything even though VCDS does record logs.

This is quite interesting and I’m extremely tempted to try. Still is a bit odd that even after restoring fuses to the instruments and ecu that there wouldn’t be a continuous check once they come online. Dang it, I’m hooked on getting this to work and now, for a third attempt, this may be my only way forward. I was hoping @Qassem would reply to this thread for some additional insight. Thank you again @Cuzoe and @Uwe!

I know this might be a bit too "nuts and bolts" for the VCDS forum, but I tried pm-ing the OP and he hasn't been here for like 6months, so gonna try throwing it out there.

I'm working on doing the KESSY rear door retrofit on my pre-facelift Golf Mk7 Variant (Sportwagen here in Canada).

I just realized that I have the older 32-pin KESSY module, so I know the part number now to buy for the new module (3Q0959435L).

A couple of questions:
1. Do the existing wires simply transfer over from the 32-pin to the 40-pin connector? Is there a guide on which ones go where?
2. Anyone happen to have the part number of the actual 40-pin connector that plugs into the 3Q0959435L module?
3. OP mentions "extra internal antenna); anyone have part number of that? Where does it mount?

@Nuje Let's see what I can do, given my Golf S has none of this fanciness

1. All the wiring is moved around, I'll send you some schematics
2. 4H0906231
3. In looking at diagrams I see the same number of body (non door handle) antennas whether 32 or 40 pin.
- 32 pin shows R136 (Rear Bumper), R137 (Vehicle Interior Luggage Compartment), R138 (Vehicle Interior Antenna 1)
- 40 pin shows R136 (Rear Bumper), R138 (Vehicle Interior Antenna 1), R139 (Vehicle Interior Antenna 2)

If I were a gambling man (and I am) I would bet for a Golf/Variant R137 = R139. Oddly the diagrams don't show a location for R139. I only looked at Golf/Variant diagrams. Maybe on a larger vehicle the 40 pin module supports 4 body (non door handle) antennas, and presumably they would be R136, R137, R138, and R139.

You need an additional 3 pins at the module for each door handle (touch sensor, antenna pos, antenna neg). So going from 32 pin to 40 gives you 8 additional pins which is enough for two more handles and one body antenna. Then again, on a Golf all the pins aren't used on the 32 or 40 pin.

Awesome - much thanks!!!

I'm currently still working through everything on this as I've installed both handles, wiring, and the connector. I have the pin swap diagram that I've come up with based upon the Erwin diagrams between the MK7 (32-pin) and MK7.5 (40-pin), which was verified correct by the master tech that I'm working with at my local VW shop after scanning with ODIS. I can share that if you'd like. What @Cuzoe stated is correct with the antenna. Now for the downsides: I've worked with that local dealer who is open to modifications and a local mod shops that have performed a number of DAZA swaps, meaning they are vey familiar with ODIS, and neither were successful in adapting the used KESSY module. They weren't able to adapt the module, as I later found out, likely because of this. I recently talked to the master tech at my dealer and was curious about going the same route with a new KESSY module but he was not confident with that either as we would have to load a MK7 dataset onto it which may not work with the MK7.5 40-pin module. He was going to talk to a contact he has on the VW/ODIS side to see what options there may be. With that article post-dating this post, I think users trying to this mod now may run into more hurdles. As an aside, humble mechanic has two videos (one and two) for doing this mod (which was done on his MK7.5).

I've heard about this, and read about others running into it. But I've also read about shops being given approval. No guarantees of course, but I assume the application is so VAG can, to their best of their ability, limit the usefulness of stolen parts.

The cynic in me says they also want you to buy new parts from them... but then it's not like they are in the retrofit market anyway... so we (retrofit interested parties) are collateral damage.

I agree with buying new parts although I suppose that would be under the pretense that VW has given you approval to install/upload an out-of-spec dataset and module in a car it wasn't originally intended. You were able to do this with the MIB2.5, right? I sometimes wish I would have explored that path a little more thorough despite the increase in cost.

Thanks for the info, @Kushdaiin! I'll definitely take that wiring swap diagram.
A new KESSY module isn't crazy-expensive, so I'll probably do the silly thing and get one of those and see how far I can get with it.

Cuzoe said:

1. All the wiring is moved around, I'll send you some schematics

Click to expand...

Hello. I'm also trying to do this. Can you help me with those schematics please?
Handles are already installed but to my understanding there's a completely different scenario (mk7 vs mk7.5) between 05-Acc/Start Auth. and other modules (4B-Multifunc. Module and/or 2B-Steer. Col. Lock ?)

Basically, the 05-ACC/Start module has to get replaced with a 40-pin version (part number 3Q0959435G - superseded since to "N", I think).

Then you have to move the existing wires in your 32-pin connector to a new connector (4H0906231), and THEN add in the additional KESSY rear door wires to that connector. (And do all of the coding and firmware writing to the new 3Q0 module to get it mated to the car and do the key-matching).

It'd sure be nice if there was an MQB car out there that had KESSY rear doors *and* the 5Q0959435 module.
Unlike my Mk7 GSW, my wife's A3 e-tron has rear door handles that look identical to the KESSY handles on the front door....almost like they rear door handles are KESSY-compatible (?).

It's just three additional wires (plus ground) that have to be added to the connector, if I remember correctly from HumbleMechanic's video, and my existing 32-pin connector has the room.

I'm not entirely convinced it's possible just by moving from the T32 to the T40. There are some functions/wires which are no longer served by the 40-pin version.
Also, having room in your 32-pin connector isn't helping at all as there's no physical pin (on the old module) designed for the rear doors.

Yeah - of course, that's the bigger issue: having wires on the connector is easier enough, but having that mate with something on the module itself is a whole other issue.

The reason I was looking at adding those wires to that 32-pin was mostly to have some reversibility to the re-wiring in the event that things don't go well.

All existing + new wires in 32-pin then extend wiring from that to the 40pin connector.