Audi Concert and Chorus volume problems.

[delambo]

These units suffer with a common problem of uncontrolable volume.  You sometimes turn the volume down and it goes up full, sometimes it goes down full, other times it does just exactly what it wants to do!

REPAIR:

Replace Motorolla 68hc705b16 with 68hc705b32 with modified dump (for permenant repair)

Part available from http://www.sapsuk.com

[M1DJF]

These units suffer with a common problem of uncontrolable volume.  You sometimes turn the volume down and it goes up full, sometimes it goes down full, other times it does just exactly what it wants to do!

REPAIR:

Replace Motorolla 68hc705b16 with 68hc705b32 with modified dump (for permenant repair)

Part available from http://www.sapsuk.com

i found if you reprogram this mcu it cures the problem with out replacing  mcu

[delambo]

Quite right, but this is only a temporary repair.  The problem is caused because every turn of the volume control is recorded in a memory table in the eeprom, when the memory table is full it goes beack to the start of the memory table but cannot over write so it follows the proviosly stored volume levels.

Re-programming will clear the memory table but it will become full again.  My replacement processor will not have this problem.

[yogi972]

Hi there,
My wife's tt has the ol' volume prob, and searched the web for ideas on how to repair

Im pretty handy with a soldering iron.. (sparky)
is this a repair i can do myself eg. put new chip in
will it be programmed ready?


I tried the link you provided but the site is undergoing maintainance :(

of am I just best sending the unit off somewhere (which I cannot find around the Midlands) (uk)

cheers muchly

Mick

[delambo]

Hi,

I can supply you a processor only for £45 + p&p (about £2) but it comes without warranty for supply only due to the technical nature of fitting it.

I can supply and fit the processor for £55 + p&p (about £7) and it comes with a 1 year warranty.

You can pay by paypal, let me know what you want to do.

If you want to fit it yourself you really need a hot air or IR rework station as the chip is a plcc52 (52 pins surface mount) as per pictures below.

[breakfast]

thanks for this helpful information

[mtl]

i found if you reprogram this mcu it cures the problem with out replacing  mcu

Can you describe the procedure in details? What is needed and do you have to dismount the processor?
With what dump did you reprogram it?
Thx.

[nagybarni]

Hy,

Basicly my girlfriends TT has the same trouble, and i just want to make sure, if i buy a new eeprom and replace the old one just by soldering it, it will work fine? it doesn't need anything else, programing or stuff like that?