Gearbox Malfunction :(

[Keymainey]

a module 0b5927321f and a harness 0b5321391a not sure what to do... they are calling me back with a price for a used trans.

Were you able to drive around with the new module for a short amount of time or miles?Or has the issue has been there consistently?

[fastboatster]

so i brought my car into the shop - they replaced my gear selector module which is what was throwing the codes and everyone thought was the issue. same code re-appeared and car goes into limp mode. they then thought it was possibly a faulty module. They installed another one and same issue - car goes into limp mode after it gets driven a few miles.
They cant get any other codes that are being thrown to see if there is something else going on. so the only idea left is to put in another transmission.
any thoughts on other possible issues? they said my trans looks fine, my car has 54K mech unit they say looks fine as well.

this sucks. as mentioned, does it go into the limp mode immediately or after some miles?
P.S. I see, it does it after some miles. did they clean the magnets that sensor is reading the position from and the magnetic wheels it uses to read the rpms? what codes are they getting now? is limp mode really related to the sensor?

[audis4culver]

so it throws the same codes after the car warms up. he is not getting any fault codes for any other sensors nor the mech unit. so he thinks another tranny will fix it. i havent asked him about the magnets and those sorts of details... i also am by far no expert on this detailed stuff either. i guess i am relying on him at this point to tell me.
what part of a tranny could go bad... is there not a way to save the trans and just replace parts of it? i dont know enough to ask the right questions.
goes into limp mode after the car gets to operating temperature - to me this all sounds more like some other sensor in some unknown place.

what does a used low mileag trans cost?
this shop is relatively knew to me.. but they have take this trans apart twice now to do the selector module - at no additional cost to me.

- - - Updated - - -

Were you able to drive around with the new module for a short amount of time or miles?Or has the issue has been there consistently?

they said they drove it 15 miles and then got the same codes again. went into limp mode like before.

[Keymainey]

It honestly sounds like the same sensor and harness combo. Especially since that's all they are getting codes for. I would just check with them that they replaced gear fluid in there too (not trans fluid), cleaned in the trans and magnets as stated above (something could be obstructing), clear all codes and perform adaptations.

Hopefully you dont need a new trans but for what I've seen for trans, they were $1.5k to about $4k. Landfill usually sells his for around $2k, plus freight of course. Unless you find one local. Try and find your same trans code for an easier swap. From Audi, apparently they have slight differences in models and generations.

This is the first that I have heard that the sensor replacement didn't work. I currently have almost a year and about 7k on mine and haven't had the issue again.

[audis4culver]

It honestly sounds like the same sensor and harness combo. Especially since that's all they are getting codes for. I would just check with them that they replaced gear fluid in there too (not trans fluid), cleaned in the trans and magnets as stated above (something could be obstructing), clear all codes and perform adaptations.

Hopefully you dont need a new trans but for what I've seen for trans, they were $1.5k to about $4k. Landfill usually sells his for around $2k, plus freight of course. Unless you find one local. Try and find your same trans code for an easier swap. From Audi, apparently they have slight differences in models and generations.

This is the first that I have heard that the sensor replacement didn't work. I currently have almost a year and about 7k on mine and haven't had the issue again.

yes - they replaced these items... twice.... module 0b5927321f and harness 0b5321391a

the work order also lists dual clutch trans fluid multi dctf # 3374650246239
and then gear oil mt-90 75w-90 gl-4 1quart. not sure if this one is gear oil for the trans or not. doing all this they also replaced my vacuum pump with some oil cooler hoses.
also rear differential service.

ugh.... dont know what to do. low mileage car.. I cant even sell it right now if I wanted so.

[fastboatster]

Hmm, one quart of gear oil sounds low, if they tore down the entire trans then both atf and gear oil would be drained out. Gear compartment takes about 4qts if I remember correctly, so maybe they reused the oil gear oil or just didn’t put enough and it got smoking hot? Unless I’m reading too much into the work order.

[Keymainey]

Check this out
https://forums.ross-tech.com/index.php?threads/7680/

Also have them check out the clutches, if those are still good then I have no idea either. That's just all I know from my own experience, research and what my shop told me.

[Keymainey]

Hmm, one quart of gear oil sounds low, if they tore down the entire trans then both atf and gear oil would be drained out. Gear compartment takes about 4qts if I remember correctly, so maybe they reused the oil gear oil or just didn’t put enough and it got smoking hot? Unless I’m reading too much into the work order.

I believe it says 4 1 quarts, but I could be wrong. That is also low based off of the tsb. It calls for 5 qts.

[audis4culver]

so i was just reading some other posts about this.... you all were in some of those as well. thanks so much for all this help.
so if i understand correctly, this dsg trans needs both trans fluid and then gearbox fluid. I agree at 1 quart of gear box oil that this is low. are we thinking this could possibly be a culprit? used the wrong fluid or not enough ?? i will ask when they call.

- - - Updated - - -

Check this out
https://forums.ross-tech.com/index.php?threads/7680/

Also have them check out the clutches, if those are still good then I have no idea either. That's just all I know from my own experience, research and what my shop told me.

they took the trans apart and said the clutches are in great condition. trans is good.. no shavings .. nothing.

[fastboatster]

I believe it says 4 1 quarts, but I could be wrong. That is also low based off of the tsb. It calls for 5 qts.

I thought it was referring to GL-4 which is a gear oil spec. As in, say, Red Line Synthetic Oil. MT-90 75W90 GL-4 Gear Oil

[audis4culver]

I thought it was referring to GL-4 which is a gear oil spec. As in, say, Red Line Synthetic Oil. MT-90 75W90 GL-4 Gear Oil

this is all i see on the order
7 qts dual clutch trans fluid multi dctf
1 q of gear oil mt-90 75W-90 Gl-4

i am wondering if this fluid situation is the issue. that certainly would be simply amazing... cant get my hopes up though.

[audis4culver]

this is all i see on the order
7 qts dual clutch trans fluid multi dctf
1 q of gear oil mt-90 75W-90 Gl-4

i am wondering if this fluid situation is the issue. that certainly would be simply amazing... cant get my hopes up though.

na..they said they filled it correctly... left if off the order and didnt charge me for it.

[fastboatster]

this is all i see on the order
7 qts dual clutch trans fluid multi dctf
1 q of gear oil mt-90 75W-90 Gl-4

i am wondering if this fluid situation is the issue. that certainly would be simply amazing... cant get my hopes up though.

fingers crossed. you can ask them how they refilled the gear compartment. if it really had 1 qt then they probably need to put another gear sensor in because the other one is fried again
P.S. crap, they filled it correctly

[Keymainey]

Yes there are 2 different oils (what they are called on sites are very similar) If the part number was , then its the correct fluid. I believe the sensor is actually in the area of the gear sensor and the clutches are in the atf fluid.

Fluids are very important, hence the reason for changing them so frequently in these transmissions to keep them from having so much issues. If the wrong fluid is used it wont do the same job that it's supposed to do. Also if it's low/dirty, it could also not being doing the job its supposed to causing increased friction, wear and HEAT. From what I read, dirty fluid and heat is what causes this issue in the first place.

Fluid found here, and quite expensive. Part number G052513A2
https://www.fcpeuro.com/products/vw-...YaAqWFEALw_wcB

I'm not sure if they used the right fluid as its just the type there and not part number. I found some other fluid that has a different part number but same oil type as you specified but not for our transmission. Everything I see is that's used for 6mt and front diff.

When I got all my stuff done, I researched and sourced all parts myself with the updated stuff. I all off the part numbers from the tsbs.

[Keymainey]

I thought it was referring to GL-4 which is a gear oil spec. As in, say, Red Line Synthetic Oil. MT-90 75W90 GL-4 Gear Oil

You're right, I was skimming. Then yea seems not right then. I know you had this issue, and if I could recall correctly, you did the job yourself? The fluid they used, is that the same type you used?

[fastboatster]

You're right, I was skimming. Then yea seems not right then. I know you had this issue, and if I could recall correctly, you did the job yourself? The fluid they used, is that the same type you used?

I had a shop do it for me, I also tore down the trans I thought I'd just have them replace mine with but it had rusty liquid in the gear compartment so was no go. The one time I pulled the trans down myself was for changing the clutch cover and DMF a few months after, there was no way I could pull that thing from under the car to get the sensor done myself. Had it filled with OEM gear oil when the sensor was done but also spilled a lot of gear oil later and topped it off with gl-4 fluid