What does the service message TOT.PART mean

dash board may have come away, there is a wire that feeds tot he dash that tells the dash that voltage is being made anything below 12 volts would indicate there is not enough voltage, it could also be the connection on the alternator, there is a single thin wire that goes into the wiring and goes to the dash this is the feed wire to tell the dash what voltage is being made, sometime this connection can get weak and not contact properly so the dash would indicate no voltage being made, it would be best to replace the connection.

you are going to have service manual like the dealer have, because its going to have all the special tools you are going to need to remove and install, plus all the diagrams, how everything is put together and when you are install the new part you dont end up with a few extra screws and when you go to use it and it does not work properly. is the ignition switch on the dash board or is on the stirring column, if its on the dash board it is held by screw and big nut on the inside panel, under the dash.
if you are doing a stirring column you need the proper tools, know where the release so the stirring wheel unlock, than remove the covers, than the ignition that the key goes into.

it been a few years since i had to do that type of work, about 20 yrs ago. and i figure it is lot harder to change it 20 yrs ago to day standards.

good luck rod

Power steering..check fluid levels or leaks.

Call a local mechanic to have a look ,maybe even the dealer ,never had a problem like this but it doesnt mean i couldnt sort it but from spain its difficult as i need my head under the bonnet/hood to get some idea ,but check the + battery terminal as it could a wire loose on here or its broke in the connection if nothing is happening as this supply would be for the power distribution box,right dinner on the table ..must go

Take to dealer,warranty will cover it.

the problem is caused by a brake light switch look under you dash on the brake pedal, the switch needs replacement

For Audi A4 model 2003 1.9 TDI 131 HP the board computer message ,,Service in 2400 km 29 tagen" means: Service due in 2400 km, or in 29 days - which one: 2400 km or 29 days will be first covered. It's very simple!

The voltage might be low off of the alternator or the battery could be shorted out.

Right away. Since ignoring an oil change requirement could cause an engine damage.

2 suggestions:

(1) I would suggest someone scan the ABS system for codes. I Have an '03 silverado 2500HD Crew cab, and it needs an EBCM (Electronic Brake Control Module) "ABS module". "Service Brake System" message on dash, ABS and Brake warning lamps lit as well. May be the R/F ABS wheel speed sensor, but what you described happen, shouldn't have caused damage to it.
(2) If the aftermarket rim and tire combo are larger than stock (larger overall diameter), then this may affect the way your PCM functions. You can reprogram the PCM to recognize larger diameter running gear so trans shift points and the speedometer and such can function properly.
I hope this helps.