There have been Macan instances where the clutch fluid temperature sensor has failed (located in the vertical board), and replacement of that board fixes that issue. But, open circuit connections to the solenoids were usually only a problem with earlier production boards, before this transmission was used in the Macan.

Concerning the Chinese boards that caused many DTC codes, those boards must be defective, with open circuit connections or incorrect connections between the TCU plug and the solenoid contacts. If the TCU can't measure continuity to a solenoid, those "Valve Electrical Fault" codes are set. There is no sophisticated "authentication" going on. If the Chinese board manufacturer builds them correctly, they will work fine.

 

@FRUNKenstein and @nycmacanguy
were you able to fix your respective issues? Updates would be great.

 

Nope - my issue seems to be failed k2 clutch. I am waiting for the new clutch pack to arrive from germany.

 

Quick update from me: I ordered new VAG solenoids from Maktrans on Monday, 9/30/24 (although late in the day, so really 10/1 for them). I reached out to them Friday, 10/4/24 to ask if I would get a tracking number as I hadn't received anything stating they were shipped. I finally got a message this morning (10/8) that they shipped them via FedEx. FedEx tracking shows a label was printed this morning but the package not yet received by FedEx in Poland. That's a little disappointing that it takes a full week to ship out some solenoids since they were shown to be in stock. Hope to have them soon.

As for the rebuilt Mech unit I bought from Sheng Hai, I have 3 rounds of emails with their customer service about trying to return the unit for a refund. They want me to replace the clutch. I've seen several other posters on Audi forums state that they got talked into replacing the clutch, only to find out that it didn't fix the problem. Today I sent them a screenshot from their own troubleshooting guide on their website stating that a P17D8 code can normally be fixed with a Mechatronic rebuild kit, so I am not inclined to replace the clutch until I rebuild the Mech unit with new OEM parts. I told them that I hope to receive the new parts soon, and if after installing them I still get the same P17D8 code, then I would consider a clutch replacement. I did ask them that if the clutch were indeed overheating and causing the problem, then wouldn't my transmission oil temperature be higher than 72 degrees?

 

Have you checked the clutch slip values?

 

That’s disappointing from shanghai. If they give you more pushback, you can send them the attached TSB. Clearly states the error is due to faulty plates.

 

Does anyone know what the torque specs are for the valvebody separation plate? I can't find them.

 

I did mine up to the same torque as the mechantronic mounting/attachment bolts - I believe it was 10ft/lb. I couldn’t find a spec anywhere but that seemed sufficient especially given the number of those bolts.

 

So separator plate was absolutely fine so I put it all back together with the new control boards and solenoids. Transmission forks were all adjusted into neutral with 32 mm spacing on the hooks that come off the mechatronics unit.

Now that everything is back together the car won't start. I'm getting codes for the transmission not communicating with the car. I checked the plug several times and it's a solid connection. Now I'm stuck. Any ideas?

 

C12004 no communication with transmission control unit

That's what I'm getting

 

C12004 no communication with transmission control unit

That's what I'm getting

That has to be the connector - did you lock in the receptacle that’s held in with one bolt? That thing was really annoying to get fully seated. It pulls the mech connector up to the transmission housing for it to mate with the harness correctly.

 

Back when I did mine, I made sure to thoroughly clean and lightly lube both the connector and the locking sleeve as well as orifice on the gearbox it slides into.

It all rotated and locked into place like butter.

 

Ohhhhh, mine doesn't look like that.


So glad you took a picture of it.

 

Update: car shifts better than ever and drives as it should. Thanks again for the help.

 

Ohhhhh, mine doesn't look like that. So glad you took a picture of it.

That's the factory harness (female) which twists onto the outside of the locking sleeve, which internally, grabs the (male) internal connector on the mechatronic unit, pulling the two halves of the connector together. What does your connector look like, if not like mine?

Update: car shifts better than ever and drives as it should. Thanks again for the help.

So what was the issue exactly? I assume you did not have it installed properly?

 

That's the factory harness (female) which twists onto the outside of the locking sleeve, which internally, grabs the (male) internal connector on the mechatronic unit, pulling the two halves of the connector together. What does your connector look like, if not like mine?



So what was the issue exactly? I assume you did not have it installed properly?

The locking sleeve is the same as yours, I just lacked the attention to detail in how it's supposed to be installed. The shifts are crisp, smooth, and flawless now. Before the repair it would slam into gears (either too early or very delayed) and it was sloppy enough where I'd leave the car in manual and shift because it was so bad.

I noticed a fair amount of metal flakes in the fluid though. Not enough to be alarming, but enough to cause some concern. There was also a flake or two of what looked like gasket material, but no idea where it came from.

 

Where do you think the flakes come from ? I have seen this is my pan on a fluid exchange. I have normal operation currently

 

Initially, I thought it may have been caused by the faulty shifting from the bad mechatronics unit. Without doing a complete transmission teardown I can't really confirm where the flakes are coming from.

 

clutch plates ?

 

Maybe. I'll be trying to rebuild the trans when I figure out how to make it handle more power.

 

Still trying to fix my Macan.

Quick recap: After the first repair (just swapping in a new separator plate to fix the missing gasket material), I got the P17D7 Clutch 2, pressure - above limit value error code. You can disregard the 2nd and 3rd repairs as I clearly didn’t have the clutch forks hooked up properly. The fourth repair installed a Sheng Hai Chinese rebuilt Mech unit. The car drove well all the way to 70 degrees oil temp, but then the next day, once thoroughly warmed up (meaning 72+ degrees) it threw the “No R-gear, Possible to drive on” yellow dash light and I got code P17D8 “Torque limit due to clutch temperature”. The 5th repair swapped out the Sheng Hai remain Mech unit and replaced it with my original Mech unit with Amazon Chinese rebuild kit solenoids (N436, N440 & N472) & PCB 1 & 2, which yielded the immediate P17D4 code (which Audi forums say is a bad N472). Sixth repair swapped out Chinese N436, N440 and N472 solenoids for (apparently rebuilt) Maktrans solenoids N436, N440, N471 and N472, leaving in the Chinese PCB 1 & 2. Result was code P17D0 "Clutch 2 - slip too high" and P2789 "Clutch Adaptation - adaptation limit reached."

More in-depth recap:
Original Problem:

"Fault Of The Engine Control Unit. Gearbox fault possible. No R-gear. Possible to drive on" warning on my 2018 Macan GTS that I just bought. It drives fine until it warms up, then it starts jerking, then begins skipping gear 4, then skipping gear 2 and 6, and finally the above light comes on and reverse doesn't work.

I did not write down the trouble code.

First Repair 8/29/24:

Swapped out the separator plate on my original Mech unit with a new one from Sheng Hai. The old one was missing a section of paper gasket on both sides in the usual spot.

Result:

I attempted to recalibrate the transmission. I recalibrated it last week thinking that might help before I had to tear it apart, and my Foxwell NT809BT bi-directional seemed to do the recalibration (I heard strange noises from underneath and it walked me through moving the gearshift from P to N and back). But, last night, my scan tool was only having me go through verifying that it was in Park when I had the gearshift knob in Park. So, I don't think it recalibrated.

I started the car back up after trying to recalibrate and put it into Reverse. There was a noticeable jerk when the car went into Reverse. It did engage Reverse, but only for a few seconds before throwing a transmission malfunction light telling me there is no Reverse. It was throwing a P17D7 code, Clutch 2 pressure too high. Reverse was non-existent. I managed to get it back into the garage and called it a night.

The next day, I warmed up the transmission and double checked the fill level. I ended up adding about 1/3 liter more fluid. I got the transmission temps up to the mid 50s and drove it around the neighborhood. Reverse still only works for a couple of seconds, and the forward gears are jerky. But, it didn’t throw a transmission code and I never got any transmission warnings. On Friday morning, it was throwing a P17D7 code, which can be caused by low fluid level, apparently.

After my new Otofix D1 Lite arrived, I went through the calibration process. For some reason, it wouldn't do step one of the calibration: calibration of the selector level position and transmission range sensor. However, my Foxwell NT809BT was able to do that before. So, after several tries with the Otofix, I went on to step 2 - calibration of the distance sensors and step 3 - adaptation of the clutch bite points. The Otofix went through both of those calibration steps just fine. Unfortunately, after driving around for a while, the same warning light came on ("No R-gear. Possible to drive on.") and I got the same P17D7 Clutch 2, pressure - above limit value. So, I parked it back on my rack and called it a day.

Second Repair 9/15/24:

Pulling the Mechatronics units out to install the Chinese rebuild kit from Amazon ($228.54) with new boards and 3 solenoids (N436, N440 & N472).

Result:

I made the problem worse. Now, I can't get the transmission to take a recalibration (necessary after pulling the Mechatronic) and it is giving me 2 malfunction codes that are different from the one I had before. In retrospect, I believe I missed getting one of the 4 shift solenoid hooks into the shift forks, too. I also noticed 2 days later the selector module electrical contact pins for PCB2 were not fully seated into PCB2 (which I had replaced myself when I installed the Chinese Amazon rebuild kit). As I didn't realize I had self-induced either of these problems at the time, I decided to order a rebuilt Mechatronics unit directly from Sheng Hai ($535 delivered).

Third Repair (9/24/24):

Next up was the Sheng Hai Chinese remanufactured Mech unit. I am hopeful that Sheng Hai (the company where I bought the separator plate and that the remanufactured Mech unit) is maybe a different and higher quality source of parts than the one I bought my rebuild kit from Amazon.

Result:

Installed the Sheng Hai Chinese Mech unit, and I now have 2 error codes that immediately return when I clear them: P2837 "Distance sensor 2 -signal implausible" and P283C "Distance sensor 3 - signal implausible". I discovered the next day on the 4th repair that I missed getting the hooks from the gear selector solenoids 2 & 3 to seat properly into the shift forks.

Fourth Repair (9/25/24):

The good part: I confirmed that I indeed had missed clutch forks 2 & 3 when I installed the unit previously. Dropped the rebuilt Sheng Hai Chinese Mech unit, adjusted the shift solenoids, moved the shift forks in and out and left them in neutral position. Re-installed the same Mech unit making sure the clutch forks were all engaged.

Result:

Refilled, started car, and the previous P2837 & P283C codes were gone.

I attempted calibration of the transmission. Step one (Selector Level & Range Sensor) calibrated successfully. Step 2 (Distance sensors) would not calibrate, I tried it at least 10 times and gave up. Step 3, Adaptation of Clutch Bite Points calibrated no problem first try.

I went for a drive. Car shifted beautifully. Drove around for quite a while, got the transmission fluid temp up to 70 degrees and went to bed (about 2:00 am) thinking that I finally fixed it. Got up the next morning to drive it to work. About 6 miles into the drive, got the "No R-gear, possible to drive on" warning light and the car felt like it was going into and out of neutral. Nursed it back home. Pulled the code: P17D8 Torque limit due to clutch temperature. Fluid temp was 78 degrees, so it wasn't overheating. Online conventional wisdom says cure for this appears to be replacing the plastic "circuit boards", which one would think would have been done when the supposedly rebuilt Mech unit was rebuilt.

As I now knew that I had created 2 problems (missing shift forks and not seating the pins into PCB2 properly) when I first installed my original Mech unit after installing the Amazon Chinese rebuild kit, I decided to next swap back in my original Mech unit (again rebuilt with the Amazon Chinese rebuild kit with Chinese N436, N440 & N472 solenoids and PCB 1 & 2).

Fifth Repair (9/26/24):

I replaced the Sheng Hai reman Mech unit with my original Mech unit that was "rebuilt" using the Amazon Chinese kit (2 PCB boards, N436, N440 & N472 solenoids).

Result:

Result was disappointing. It did take part 1 and 2 of the calibration process, but failed to complete part 3. Also, it threw a P17D4 code (Clutch valve in gear train half 1 – mechanical fault) right off the bat (I never even got it off the 4 post lift).

The Audi forums say that the culprit for P17D4 is the N472 solenoid, which is one of the two small solenoids on the bottom part of the Mech unit. I replaced N472 when I installed the Amazon Chinese rebuild kit. So, it may be a bad solenoid from that kit. My concern is that if I replace just that N472 solenoid, it might still have some other bad parts.

Sixth Repair (10/23/24)

I ordered what were listed as brand new OEM VAG solenoids N436, N440, N471 and N472 from Maktrans in Poland to install on my original Mech unit (not the Sheng Hai reman) to replace the Amazon Chinese rebuilt kit solenoids (N436, N440 & N472). I did this because even though the Audi forums say the N472 solenoid is the likely culprit for P17D4, I am concerned that once the fluid warms up, that another problem will surface with one of the other solenoids. It was throwing P17D7 codes after just the separator plate was replaced (after Repair 1, before the Chinese rebuild kit was used). Sheng Hai’s troubleshooting guides says that the 2 PCB boards and 3 solenoids (N436, N440 & N472) rebuild kit will fix P17D7. So the Chinese kit may have fixed P17D7 but a faulty Chinese N472 may have caused P17D4. I should probably have also ordered new OEM PCB 1 & 2, N433, 434, 435, 437, 438 & 439 solenoids just to be sure. But, Maktrans PCB 1 & 2 ($104 for the pair) look to be made in China anyway (and I already have new Chinese PCB 1 & 2 installed in my old Mech unit). Maktrans does sell N433, 434, 437, 438 (new VAG $81 each) and N435 & 439 (new VAG $66 each) solenoids. But, since all of the OEM Audi kits consist of N436, N440 & N472 & PCB 1 & 2, I was betting that’s where my problem lies. So, once installed in my original Mech unit, I’ll have new Chinese PCB 1 & 2 and new OEM VAG N436, 440, 471 & 472 solenoids. The conventional wisdom is that it’s the solenoids, not the boards that are the bulk of the problem, so that's another reason I decided not to replace the Chinese PCB 1 & 2 with OEM boards.

Received the Maktrans solenoids N436, N440, N471 & N472 on 10/18/24 (ordered 9/30/24). They were not new units, despite Maktrans’ website listing them as new (they were wrapped up together in plastic wrap and were covered in oil).

Installed the Maktrans solenoids last night. Went through calibration steps 1 & 2 fine, but failed to complete step 3 (just like after the 5th repair). It would give me a momentary “Basic setting routine has ended correctly”, but then continue to run the routine and ultimately give me an error message.

I tried this multiple times until the oil temperature reached the maximum 60 degrees that would allow the calibration to run. Since it gave me that momentary “Ended Correctly” message, I decided to try a test drive. Shifting was poor from the start. As soon as the transmission oil temp hit 72 degrees, it threw the same “No R-gear, Possible to drive on” yellow warning on the instrument panel. The codes thrown were P17D0 “Clutch 2 – slip too high” and P2789 “Clutch adaptation – adaptation limit reached.” I took photos of the clutch values on the scan tool: Clutch 1 slip 7.117 bar; Clutch 2 slip 9.374 bar; Clutch 1 lower adaptation point 3.106 bar; Clutch 2 lower adaptation point 2.84 bar; Clutch pressure, clutch 1, 0.02 bar; Clutch pressure, clutch 2, 0.02 bar; Setpoint torque of clutch 1, -500 Nm; Setpoint torque of clutch 2, -500 Nm.

It is interesting that I did not get the P17D4 error code after the 6th repair like I did after the 5th repair (which came on immediately upon starting). So, swapping in the Maktrans solenoids apparently corrected that (bad Chinese N472 solenoid?). But, the shifting problem remains. Based upon the Clutch Slip values listed above (Clutch 1, 7.117; Clutch 2, 9.374), it appears that I may indeed need to replace the clutch pack.



Thoughts?

 

Looks like you have unlimited time and patience to keep repairing this instead of putting in quality original parts in one go and be done with it. I’m out of suggestions - perhaps others may have ideas.

 

Point taken.

In all fairness, the first time dropping the unit, I could have just replaced all of the parts. But, I wanted to test that theory on the missing gasket paper, so that's all that I did.
Also, the premise at the start was to see if there was a quick, cheap fix. So, yes, there is self-induced pain, no doubt. This isn't my daily driver, and although the ultimate goal is to fix it, I also wanted to experiment a bit to find the actual failure point, too.
The question now is whether to order new OEM PCB 1 & 2, N433, 434, 435, 437, 438 & 439 solenoids. Or, based on the current codes and clutch values, is it likely that it really does need a new clutch pack.

 

Buy the parts from the link I sent you - all new Audi plates and all six solenoids bottom area are 750 usd delivered in 2 days. Which is price of only plates feom fcpeuro. No affiliation with the vendor - am a happy customer. Why aren’t you fighting with maktran for sending you used stuff.

 

Full Calibration won’t go through if there is any fault in the system.

 

So what were the error codes when you first had problem? Don’t remember anything to do with clutch pack - only mech unit. You might be attempting to fix something that isn’t broken yet.

 

The problem is I have seen some consensus online that a faulty mechatronic will quickly burn the clutch out. It’s possible the original issue is now resolved but the clutch is already gone. I think that’s what happened with mine. The difference in pressure between 7bar and 9bar is pretty significant.

 

That’s correct if the car has been driven for some distance with improper calibrations. So did the new clutch pack fix your issue?

 

I don’t have a lift so can’t pull trans myself - dropping it off at my mechanic next week. Will report back.

 

I would buy a used TCU from ebay and get it cloned....

 

I read through your ordeal with the TCU but I don’t think the behavior was the same. Did you ever check clutch slip values while you had the issue? I can feel the clutch slipping I don’t think that would happen if a pressure sensor was failing.

 

This morning, I hooked up my Otofix D1 Lite scan tool to my 2015 Macan Turbo, which is my daily driver. I wanted to compare the clutch readings from it (with a healthy transmission) to the '18 GTS that's the subject of this thread. Clutch 1 slip was 6.644 bar; Clutch 2 slip was 6.429 bar (versus Clutch 1, 7.117; Clutch 2, 9.374 for the non-functioning '18 GTS). The 2015 Turbo has 83k miles versus 98k miles for the '18 GTS.
Lower adaptation points for the 2015 Turbo are 2.878 & 2.31 (versus 3.106 & 2.84 for the '18 GTS).
Then, I ran through all 3 steps of the calibration on the 2015 Turbo (and it went through all 3 steps easily). After calibration numbers for the 2015 Turbo were Clutch Slip 6.695 & 6.42; Adaptation points 2.869 & 2.315. So, all numbers pretty consistent pre & post calibration.

@tallkyle , on your recommendation to have the TCU cloned, are you saying to me that "The TCU seemed to be the culprit in my car, so you should try that first before replacing the clutch pack since you can do that yourself and it is a fraction of the cost of the new clutch pack"? That makes a lot of sense. I'm just wondering if the clutch slip numbers are telling me that the clutch pack needs to get swapped, or if the clutch slip numbers are due to some remaining problem with the Mech unit (including the TCU - like a bad pressure sensor). I don't know if there's a way to tell for sure without just replacing that TCU. Then, if a replacement TCU doesn't fix it, go to the clutch pack.

The good news is that I think I can pull & replace the Mech unit in my sleep now. Heck, she's watched me do it six times now, so I think my dog could do the job at this point.

 

I don’t think the TCU is the failure point for either of us - tallkyle didn’t have the same codes. I’ll let you know how my clutch swap goes.

Also, apparently you can visually inspect the clutch if you pull the mech then apply air pressure to one of the two plastic pipes to actuate each clutch. Supposedly there will be a difference between the actuation of either one that should be noticeable when you look up at the clutch from below. I didn’t do this when I had my mech out.

 

So I just found something really interesting… this FCP Euro video about the DSG says that the flywheel is essentially a service item that could cause the same symptoms I have. I suppose it wouldn’t trigger the clutch slip code though.

I already have the clutch and it would be zero additional labor to throw in a new flywheel so I might just do that too.

 

Any updates on this? I also would suggest doing the DMF while its apart to do a clutch.

 

I used this kit - this has the green things for all contact points. Buy the Audi branded kit - it was cheaper than Borg.

 

Somebody posted this link earlier in the thread

Valve body 0B5 DL501 0B5325025T 0B5325031N refurbished and tested on the car. from VAG – Buy Now for $756 USD

Buy Valve body 0B5 DL501 0B5325025T 0B5325031N refurbished and tested on the car. from VAG at $756 USD. 10 units available. Fast & worldwide shipping.

maktrans.net

This one any good? We did all the things ya'll are saying. The PIWIS may tell us more but this is the next step as far as I can tell

 

Yes, thats the one you want if you want to replace the unit as a whole. Maktrans has good testing procedures and is reputable. As stated earlier, if you order this unit, it would be my strongest recommendation to throw the two black circuit boards out and reuse/replace with genuine Temic/BorgWarner ones. That will near guarantee your success.

 

Well I've replaced everything and still no luck. My brother is saying that the second gear position sensor is not reading and it's something to do with that?

 

That position sensor is in the “tower” of the TCU. Surely you can find one second hand and get it programmed.