DSG Transmission help

[Tjscott3]

another DSG issues thread for you guys, ive done a fair bit of searching but no luck with the answers i am looking for,

picked up a 70k mile audi S4 on auction, trans was a bit jerky but drove okay. as you can guess the jerkiness got worse ( and very very harsh in reverse ) so i sent the mechatronic unit away for testing. it was found faulty and i purchased a remanufactured unit to replace it. however now ive got this in, it reversed okay down the driveway ( which was a nice change ) but when shifted into D i got a few errors, which change whenever i clear them, but the consistent one is P17D400 "valve 3 in partial transmission". the car will now show as having gone into gear, but will not move.
have i gone wrong in lining the shifters up/ have i made a mistake in assembly, or does the remanufactured mech unit potentially have an issue?
any help would be appreciated.

Cheers, TJ

[LowKeyLoki]

Did you reinstall the mech unit yourself? I’d take it out and double check the forks for the solenoids are properly set. And was the manufactured mech a full replacement of the board and the valves? I’d go into VcDS first before anything and try to run a TCU adaptation, you are supposed to do this after doing any work to the trans. Go to the DIY sticky for the DSG or search “DL501 adaptation”

[Tjscott3]

Self installed, all the forks set to the recommended measurements but if it comes to it I’ll get it back out and redo it, I’m using obd11 and have been able to do all the adaptations other than the clutch engagement points which it aborts whenever I try ( and also gives a trans warning on the in car screen )

It was a complete replacement mech, both valve body and TCU.

[LowKeyLoki]

Idk much about OBD11 but I def recommend using VCDS to do a proper calibration vs OBD11. If you plan on keeping the car long term and DIYing then VCDS is a must on theses cars. It has much more capability than OBD11

[Tjscott3]

I’ll look into grabbing vcds/ the cable to connect it, in the meantime while I’m messing about with this I’ve noticed it’s the always the clutch point adaptation that it aborts. So having looked at the clutch pressures in different gears it seems that while clutch 2 changes quite happily, clutch 1 is not, remaining at about 0.20-0.22 bar no matter the gear. Is that something the mechatronic controls directly or do I have a separate issue to hunt down?

Thanks massively for all the help so far

[Tjscott3]

Meant P-R-N-D when I said gears, as I’m not able to drive it to shift through 1-7, with the engine off I’m also getting 0.22 bar on clutch 1, with -1.00 bar on clutch 2. Which doesn’t seem right to me.

[LowKeyLoki]

Sounds like it’s either the mech board connection to the K1 solenoid is bad or the solenoid itself is bad. Probably will have to pull out the mech unit and inspect the board, look up HumbleMechanic on YouTube he has a good tear down of a DL501 mech unit and shows how he tests the solenoids for the clutches.