chrisorbics

I am trying to bring a 2001 audi s8 back to life. It runs and drives well but after becoming the new owner the check engine light is on.

1) p1815 or 18223 pressure control valve 1-n215 short to B+
2) p1114 or 17522 bank 1 sensor 2 internal resistance too large. (I just got a sensor and will install soon.)
3) p1602 or 18010 power supply (B+) terminal 30 low voltage.
4) p1392 or 17800 bank 2 camshaft position sensor 2-G163 open circuit/short to B+
5) p1624 or 18032 mil request signal:active

This car has the FBG transmission.

I am not the greatest with electrical so I am hoping the someone here has some experience with these issues. The car runs and drives great. No problems shifting. The car will not allow me to input the radio code but I am sure this is unrelated. I held the two button but nothing happens.

With the codes that I have where should I start and how can I pin point the issue?

jfrahm

Have you cleared these to see if they come back? Sounds like it might have had a low battery.

chrisorbics

Thanks. I will do that now and drive it to work. I was thinking the same thing but didn't think that would affect the P1815 which is the one that really concerns me.

jfrahm

I found a raft of crazy codes stored when I bought my S8, it had recently had a dead alternator and battery. Nearly all of them stayed gone after I reset everything. Of course the seller said it had no warning lights and when I got there, 1000 miles away, I found it had ABS, Airbag and Check Engine lit :-) So not ALL of them were lit I guess.

chrisorbics

I just went through my phone because I took pictures of the code reader and all of the codes. The first code that came up when I got the car with a different generic obd2 reader was p0748. This is pressure control solenoid a electrical. I have read that this is usually caused by dirty transmission fluid.

So I did delete all the codes and drove it 14 miles and cel came back on for p1114 o2 sensor p1815 pressure control valve and a NEW code p1835 or 18243 pressure control valve 5n233.

What I need to figure out is how to determine of this is an electrical or mechanical problem. I would like to check the tcm and see if there is an water in it. I have heard it is in the passenger interior area. I am also thinking about changing the transmission fluid and filter but I am unsure of where to buy it from. I saw a kit on blauparts. Does anyone have any recommendations for where to buy the fluid and filter. I have looked around locally and no one has the correct fluid. Amsoil claims their synthetic multivehicle trans fluid is good for this model but from what I understand this is very specific fluid and not generic multivehicle. I am just looking for the proper fluid and hopefully a reasonable price.

jfrahm

I use Valvoline Maxlife ATF. Full synthetic and it meets the VW and Audi spec. I suggest a Meyle or Reinz OEM style trans pan gasket. If you get a filter with a thick silicone gasket IMO do not use, I tried two of them and they both leaked.
For the filter just make sure you get the short neck and round pickup, the oval pickup is for BMW. There is a Meyle kit:
https://www.fcpeuro.com/products/aud...6-01l398009bmy

Probably the right filter? Can't tell from the pic but the long neck round pickup can be trimmed if need be.

chrisorbics

Well it is raining today and the car is not shifting. It starts is high gear and does not shift. I tried deleting all of the codes and no change. Not happy. Maybe water is getting to the tcm? Does anyone know where it is located?

spitanddirt

The TCM is located under the hood, passenger side, close to the windshield. You have two covers that have to be removed to access it. First one is a flimsy one that helps keep leaves out of that area and you have to pull back the thick rubber seal partially to remove it. The second cover is a hard plastic cover that should has 8-10 screws.

Google Images is your friend

jfrahm

Yeah maybe, it is in the center cowl area that floods if the center drains are plugged. See the guide on audipages to clear the drains. It's not the AC drains but the cowl drains you use a hose to blow air into.

First hit when googling "audi a8 tcu" is:
https://www.audiworld.com/forums/a8-...ation-2775788/

chrisorbics

Thanks for all the information. I am going to look at it if I have a few minutes today. Merry Christmas to everyone.