Audi A4 2.0 TFSI - TPROT and CAT monitor disable

[cocktailyogi]

Hello,

it is my first time, that I am playing with MED17 from my car and I am still learning. My goal is to disable CAT-Monitoring and leave secondary lambda-sensor and catalytic converter in place.

I have removed the ECU 8K2907115P from the car. The Software says another ECU-partnumer: 8K2907115AJ
Does anybody know, why they are different?

I have built myself a bench-flash-setup and opened the ECU without damaging it. I was able to dump flash and eeprom in bootmode.
Then I disabled TPROT and fixed checksums.

Could anbody help me finding the adress für disabling cat-monitor? Or help me with a domos-file?
And I would be happy, I somebody couls check my flash-file, if it is valid. I want to be sure, before flashing it back or moving on with it.

Thx,
Yogi

[jurebv]

this is very very hard to do without damos...you need to find bytes for cat diagnose

little info on it https://s4wiki.com/wiki/Tuning#Rear_O2_Sensors

[cocktailyogi]

Hi, I did a little progress. I tried to turn off Tprot in Winols and fixed checksums with Winols. Then I was not able to flash the the file back to my ECU with Galletto v54. I gave me some errors about checksums. Then I changed stratgey and took, my original backup from flash, edited TPROT-values in hexeditor and flashed it back. Galletto corrected the checksums for me. So I learned that for some reason the checksums from Winols are not accepted by Galletto.
But know I have figured out a way to read and write my EEprom and Flash in Bootmode and maybe via OBD.

Now I need to take car of my Cat-Monitor. From what I have read, I need to set CDKAT and CDKATSP to zero and maybe CWDLSAHK ?
What about Readiness threshold for CAT-probing. How can I get Readniss codes green?

Could anybody help me with the ROM-adresses for CDKAT, CDKATSP and CWDLSAHK. Otherwise I will buy a Damos-file somewhere. What is a good price for this? Or better buy a complete pack?

Kind Regards,
Yogi

[jurebv]

In attachment is your file with cat diagnosis off free, i have damos that matches your file if you want to learn, if you're interested pm me

[cocktailyogi]

Hi, that file has a password. How to open it?

Kind Regards,
Yogi

[jurebv]

message me

[cocktailyogi]

Hi Jurebv,

I tried to follow your modifications in my file. I had to make my own definition-file to track your changes in my file. It seems you did more than disabling CAT-Monitoring. It seems you removed secondary lambda as well. Have you removed Errorcodes as well?

My goal was to learn something about MED17 and to get rid of my Errorcode P0420. My Cat is still in place and is not cracked or seems otherwise damaged, but after 50km I am getting P0420. So I want to disable the efficency monitor.
Some my idea is to zero CDKAT and CDKATSP and seem if it works. Does this work?

Kind Rgards,
Yogi

[jurebv]

I did not remove a single error code as you did not post you had any, i just removed cat diagnostics, with my file you wont get p420 ever, i dont think you can learn anything from my file without damos as it is just bunch of single value changes

[cocktailyogi]

Hi,
I have a definition file for this ECU.
Now I have understood all your changes. You did not disable errorcodes. Sorry, my mistake.

But why did you disable more than CDKAT and CDKATSP?

I had a look at Funktionsrahmen and it seems, that those variables disable the CAT-Diagnosis. Why is it nessecary to disable Lambda-related stuff and modify the KAT-Heating Configuration?

Yogi

[jurebv]

after you answer few of my questions you will understand, wheres the second lambda located on the car? and what is cat heating's purpose?

[cocktailyogi]

Hi,
just a quick update.

I used my original file and set CDKAT and CDKATSP to zero. I did not touch the other stuff, which is related to second lambda.
Car works fine now. No DTC at all. CAT is still in place and basically works. Car has passed emmisions with no problem. The problem was, sometimes it gave Errorcode P0420. Now, MIL remains off.

I will keep you updated, if something happens.

Thx for your help.

Kind Regards,
Yogi

[jurebv]

do you know a function of second lambda?

[cocktailyogi]

From what I know it is used for CAT monitoring. From what I read it does olso additional fuel trim in MED17. That is the reason why I want to keep it.

What is your point?

Yogi

[jurebv]

Fuel trims for cats purpose, once you have bad cat its useless

[cocktailyogi]

I see, but my CAT has an efficiency issue. It does not mean that efficiency is zero. What is advantage of disabelling second lambda and disconnectiong wire?
Even if it is useless, does it hurt?

Yogi

[jurebv]

Dont need to but when doing this for customer prevents future errors and customer will not complain because mehnics tell them its cat related when they have 2nd lambda error

[cocktailyogi]

I see your point. This might be wise in case of of business.

I am doing this for myself to learn something and to fix my own problems. So the challenge was to disable only CAT Diagnosis and I succeeded with your help. If something strange happens, I will focus my view on secondary lambda.
Thx for your help!

Yogi