2003 Audi A6 VDO Unable to read EEprom using TU help!!

[AudiS4]

I am trying to modify mileage on a 2003 audi a6 vdo using clip on 93c86 eeprom using tacho universal.I checked the wires,and the adapter board are both good.However when I clip on the clip tacho universal is unable to read the actual mileage.I reads a different mileage which is incorrect.Also when i select read eeprom and show it is all zero's.I have tried doing another eeprom using the same clip with same results.Which leads me to believe the clip does not have a good contact or the port on the tacho universal which the adapter attaches to is no good or has a short somewhere.Anyone has had the same problem???The clip is brand new from pomona.All 3 crystals are shorted.i am still unable to read the eeprom and edit it in circuit.Any one have a fix for this and could tell me what the issue is i would appreciate it.

[haroutioun]

Hi Dear, did you remove the eeprom from the board? or direct you connect the clip on eeprom? it must remove the eeprom from board to read the data..
good luck...

[wiseman]

Have a look under the shrink wrap that connects the clip to the wires, some of these are poorly made and break from the clip, also try to pin out the clip and maake sure its configured correctly

[honingkoning]

I am trying to modify mileage on a 2003 audi a6 vdo using clip on 93c86 eeprom using tacho universal.I checked the wires,and the adapter board are both good.However when I clip on the clip tacho universal is unable to read the actual mileage.I reads a different mileage which is incorrect.Also when i select read eeprom and show it is all zero's.I have tried doing another eeprom using the same clip with same results.Which leads me to believe the clip does not have a good contact or the port on the tacho universal which the adapter attaches to is no good or has a short somewhere.Anyone has had the same problem???The clip is brand new from pomona.All 3 crystals are shorted.i am still unable to read the eeprom and edit it in circuit.Any one have a fix for this and could tell me what the issue is i would appreciate it.

it could be possible that the small ic on your mainboard is damaged, (it's located under your display)i cant remember the exact id number of that.
But if you have a manual there is a part which helps you troubleshooting.
Other wise you can search the forum it is there somewhere i cant remember where.

Regards Honingkoning.

[AudiS4]

I have manual but don't see troubleshooting section anywhere.Can someone upload????or does anyone ave a TU repair manual????I tried reading out a nother ic still same results.

it could be possible that the small ic on your mainboard is damaged, (it's located under your display)i cant remember the exact id number of that.
But if you have a manual there is a part which helps you troubleshooting.
Other wise you can search the forum it is there somewhere i cant remember where.

Regards Honingkoning.

[digimile]

hi
why not u try with upa programmer and put dump here and some one calculate for u.

[darrenhyland]

did you try with cluster plug adapter on back of the dash?

[honingkoning]

I have manual but don't see troubleshooting section anywhere.Can someone upload????or does anyone ave a TU repair manual????I tried reading out a nother ic still same results.

Here you go mate page 7 74hc541 needs to be replaced

[AudiS4]

thank you.I have a set of test clips on order to see if the test clips maybe will give me a better connection I also have 2 used clsuter to test and comapre if i get the same results i will replace 74HC541.Is there any way to get 74HC541 by itself instead of the whole repair kit??

[honingkoning]

thank you.I have a set of test clips on order to see if the test clips maybe will give me a better connection I also have 2 used clsuter to test and comapre if i get the same results i will replace 74HC541.Is there any way to get 74HC541 by itself instead of the whole repair kit??

You can buy them just use google and you will find a lot of suppliers,
You can also solder wires on your eep, and do not forget one thing i see that a lot members are trieng to help but no thanks to them at all.


Regards Honingkoning.

[martiboy]

Remove the eeprom from the board. Make a sw13 cable and read the eeprom again. Chances are its just your clip not making a good connection. You could also try cliping the eeprom and sqeezing tight on your clip. I use 3m clips now instead of the pomona for the ver same reason

[AudiS4]

I got my ez hooks today still nothing.I will try to do another cluster tomorrow via clip.Is there any other way to test the tacho universal to know for sure thats the problem?

[AudiS4]

I am curious if it possible for the Tacho To have a faulty 74HC541.The unit is new I have used it once.Is it possible that the 74HC541 is already no good???I would like to get this solved as most of my work is done on the bench and not in the car.Anyone have anything else to add or that I can check???ALso what do you use to desolder such a small ic and solder it back??

[honingkoning]

I am curious if it possible for the Tacho To have a faulty 74HC541.The unit is new I have used it once.Is it possible that the 74HC541 is already no good???I would like to get this solved as most of my work is done on the bench and not in the car.Anyone have anything else to add or that I can check???ALso what do you use to desolder such a small ic and solder it back??

I use pattex superglue

[Digamax]

I am curious if it possible for the Tacho To have a faulty 74HC541.The unit is new I have used it once.Is it possible that the 74HC541 is already no good???I would like to get this solved as most of my work is done on the bench and not in the car.Anyone have anything else to add or that I can check???ALso what do you use to desolder such a small ic and solder it back??

Just one advice to you:
DONT TRUST TU FOR EEPROM READING AND WRITING(especially without desoldering eeprom)!!! You can erase all content of eeprom!
Bye some eeprom programmer with pin check options (for example Elnec Memprog or Beeprog) and you never have problem.

Best regards
Vladimir