Noah Fect

An IR camera is the tool of the gods, and they are cheaper than you think. Just saying...

Olddragger

Lost the one I had and you are right. The mechatronic unit wasn't bad to replace at all. Just work. Done in my home garage on Jack stands. There is a lot of info concerning this on the Audi forums. Jus waiting on my fluid to come in trans is buttoned up. Rock Auto had a package deal for a new internal filter, external filter, pan gasket and all o rings for just $55! Using motul dctf. 8 liters for about $170. If this works, it sure will be much less than the dealership wanted lol!
After seeing everything I am concerned about temps. Taping into the coolant lines will be too difficult.......just not room to access them. I have identified some spaces on the pan that has enough internal room for a sensor.....but I don't know if the cross brace will clear. I will look at that again soon. I really don't want a sensor fitting from the transmission hanging pass the cross brace.
Y'all know what.... the more I look at the 2017 base model donor transmission and mine ......the mechatronic unit looks improved, but everything else is the same. I would not be surprised if even the clutch packs are the same? It would probably be cheaper for Porsche to do it that way.

VAGfan

The mechanical portion of the transmission (clutches, gears, selector rods, ATF pump, bearings) is fine, it is the mechatronic unit that is problematic.

Olddragger

Agreed...that is a reason I was glad to see some changes in the newer year model mech unit.
Now that I am familiar with how to do this.....if I had the part....I could do it at home in 3-4 hours. Perhaps the part will become more available soon.
I am trying my best to not develope a lack of confidence in this car.

Olddragger

Ok ...got it buttoned up, fluid in (5 liters motul first fill), noticed the battery charge was down to 11.7 volts, but cranked it anyway. Not surprised that I got the red transmission fault pop up and it went into limp mode. I shifted through the gears...heard some clunking.....clutches seemed ok....turned it off and then filled it up with 2 more liters. Red fault continues to show....in limp mode and probably what is happening is the pcm is speaking a different language than the TCM. Calling dealers Monday as the pcm and the TCM needs to become friends.
No leaks seen.
with the cat converters being so close to the transmission and the trans coolant lines....
everthough there are heat shields present....it is hard to not think that radiant heat is not adding to the temp of the transmission.
I know this is taking a long time to finish up....but work has been calling a lot lately and in sept I will be 73. It is a little harder to get off the garage floor now a days.

icemang

FWIW I had one in an '11 S4 that I put ~120K miles on and I never had a lick of problem with it. I just sold it last year.

Olddragger

The mechanical side seems to cause no problems. But I will bet you a dime on the dollar that are more problems with this transmission in the Macan than many believe. I have been observing my indie and dealership and it seems there is always a Macan there with transmission problems. The mech unit is what is doing it. Now whether it is running hot causing damage, the solenoids go bad, the TCU messes up, or the circuitry ....who knows?
What amazes me and really ticks me off about this entire thing....is Porsche will not sell you a replacement part and will not make it reasonably available the software to diagnose and to mate the parts.
I am not really upset about the transmission having a problem.....but I am really upset about how Porsche does not support a repair outside their dealers.......who really don't try to repair it. Heck if I can install a mech unit.....I would hope that a Porsche tech could do the same for a reasonable cost.
Sorry for the rant guys.... I know it is nothing new......haven't had my coffee yet....... calling dealership today to see if they will program the new mech unit to my car. Heck, I need to have my own flatbed truck! This is the fourth time it has been on one.

Petza914

What you write here is exactly why we didn't buy a Macan. Had a manual transmission choice been available in the high performance models, there'd probably be one in our garage. We've now missed our need window for a Macan sized vehicle with one of my kids already driving and the 2nd one starting this fall.

Olddragger

Actually no luck at the dealership. First I had to leave a v/m for the service department. I waited....no return call. I called again, asked the nice lady who answered I needed to speak with someone , not leave a voicemail. She found someone. Nice guy but was not believing what I was telling him. Never seen that before in the Porsche's..only Mercedes etc. He was nice about it and ok to talk too. He said he needed to have the actual Service manager speak with me about my request ( mating the mech unit to the car) and he wasn't there that day! But he would have him call me the next day (today). No call has been received. I called back.....he is still out. I get it....they don't want to deal with it. Obvious. So I spoke with my indie.and they said for me to change out the transmissions control unit to the old one out of my old mech unit. I opened it up and it does look ok. No bubbles, discoloration, or broken circuitry under a magnifying glass.
So I am pulling the mech unit once again, installed the oridginal tcu and see what happens. Wow what an adventure....and to ____ with Porsche and this dealership in Atlanta.

VAGfan

I would take the original Mechatronic, and just swap the vertical black plastic board PCB2 (where your melted clutch oil temp sensor and input speed sensor are) from the newer Mechatronic.
Then you probably just have to clear the TCU fault DTC codes from the original failure event.

Olddragger

The black board on the vertical and the horizontal ones where both overheated with signs of melting. I tried checking continuanity and the horizonal piece did appear ok an no discoloration seen on the contacts. The boards are the same part numbers so I am ok using the newer horizonal piece. I keep wondering what the heck happened. No contacts points appear overheated, the solenoids did not appear bad and all check the same. What the heck caused this kind of heat? It doesn't appear electrical? The car at wasn't under any load, wasn't towing, simple highway drive until the short drive up the mountain at slow speed....I was in off road mode but speeds never over 30 mph. Some snow on the road but there was no wheel spin, a small amount of wheel spin when I turned the car around at the cabin, no clutch slippage. Never went into limp mode. Radiator fans never came on......So what caused that heat? It had to be very hot to melt that plastic like that..

VAGfan

I don't think the origin of your melted plastic is an electrical issue, I think the ATF exiting the clutch was too hot, melting the plastic around the temperature sensor and speed sensor. Was the radiator somehow blocked when the failure occurred? Or, the clutch was actually slipping, maybe due to an ECU control glitch?

Olddragger

Radiator wasn't hot that I could tell. Always at that 200F! No blockage to the radiator present or oil coolers. I didn't notice any clutch slippage.....I did notice hard clutch grabbing after it started acting very badly. No clutch material in the old fluid.....if there would be any. It did melt at the temp sensor position the most. So therefore the question ....what caused the clutch to slip? It is just a unsolvable mystery to me. Hope I have time to button it up tomorrow and try again. Will let everyone know. Have learned a lot at least.

Olddragger

Update. The Porsche dealership Sevice Manager called this morning. He was apologetic for taking this long....they are simply so busy. He spoke with me for a long time. States my plan to swap out the TCU was my best option at this time. They would calibrate it for me or try to. It would depend if the tolerances are acceptable. We talked about what happened and like Vagfan posted he too thought it was from the clutches. He did say it was possible that the temp sensor could have went out first and caused the fluid to overheat because without that sensor the limited cooling ability of this transmission would have been further reduced. We talked about heat and it was his personnel option that there is a problem with temps of the fluid. They have had more Macan transmission problems that any other Porsche Model. He is very interested in getting readings of real world transmission fluid temperatures. (mechatronics section) . He asked me to bring what ever info I could in to share with him. That made me feel a lot better. I have to admit it has been a little bit of an emotional time. He was a master tech for 12 years before taking the job he now has. Sounded like he was very familiar with the trans.
Depending on how my little part time consult job goes today....hope to get it back together today or tomorrow.

Olddragger

PROGRESS! Completed the swap. Did first fill of motul dctf, checked battery voltage, cleared all codes I could with the Cobb unit, said a big prayer and fired it up.
SUCCESS! Transmission red colored fault massage gone! I do have the yellow warning Possible no reverse gear but ok to drive message, but I was expecting that. It is not in limp mode now of course.
I warmed it a little, changed to reverse....transmission engaged! To neural..felt good, then to Drive and the first gear showed on the indicator and it felt engaged! Woo Hoo!!
Now I just have to wait for some Motul to get here tomorrow. (It did take about 6 liters first fill). Warm it up a little and do the second fill. If all good ...reinstall crossmember, panals, then take it off Jack stands and see if it will drive. Not out of the woods yet.....but much better than before. Thank you Lord!