Christmas tree dash with music aswell

[audiv8quattro]

right after recently purchasing my first a6 (Saturday) I was happy with the experience up until today.driving along at a constant 50mph and engine light lights up, so I pull over, get my trusty (cheapo) code reader out plug it in and there's 2 codes, egr insufficient flow and engine temp sensor. So clear codes, go straight to a vw/Audi specialist and I explain the problem and tell him that a new egr valve was fitted at the end of last year with receipts to prove, he goes on to explain that the garage that fitted the egr may not have done research into why the first egr valve went wrong and just fitted new one, so I agree to book it in for egr/dpf delete and a remap on Saturday, all well and good, then I decide to go and do a bit of shopping in Brighton (big mistake) on the way over there the dash lights up like Blackpool illuminations with added sound effects, esp/abs faulty check owners manual electronic parking brake faulty and engine light back on, but no decrease in performance/braking ect so I pull over at the first opportunity, pull out my trusty code reader (again) and there's loads of codes, I photographed the codes rather than writing them all out on here I though it would be easier to show you all. So sorry for the long post but I'm in desperate need of some help. I've done a bit of research and some are saying I need a new abs module thingy. Others are saying gearbox, to add I drove to Brighton, done shopping and drove back home and no lights at all on the dash now so about 30 miles drive. Any help is really appreciated.

 

[audiv8quattro]

Forgot to add its a 2005 3.0tdi Quattro on a 54 plate if that makes any difference

 

[B5NUT]

Looking at some of the codes it could be down to the alternator (that is where the load signal is generated) or the battery is dying. When was the battery last replaced?

 

[audiv8quattro]

Thanks again b5 nut, funny enough when I go to start the car most of the time it does sound exactly like the battery is dying, and I was talking to a bloke about it earlier and he said if the battery was dying that could play all sorts of havoc with the ecu, throw up codes ect, not sure when the battery was last replaced to be honest.im going to check I have the radio code then I'll shoot to halfords and grab a new battery, is there anything else I need to do when changing the battery or is it the same as Al other cars, just replace battery and of you go? Stupid question I know but don't want to go changing the battery to find that I can't start the car because of some immobiliser or something

 

[B5NUT]

The MMI system has no radio code, it checks against the chassis number stored in the 05-Acc/Start Auth module. Everything will work fine but you have to give the car a quick drive (with left & right hand turns) to get rid of the ESP light.

 

[audiv8quattro]

Right thanks mate, got a new battery (£100) later from halfrauds, replaced the battery, car still sounded like it was struggling to start but that was only the first time it had been started with the new battery, as you said the esp light was on but also the electronic handbrake malfunction came up twice but if I press the handbrake button it went straight of again, then didn't come back on. Wondering if it was just where it was a new battery???

 

[RoyC]

You should recode your new battery or the brain thinks it stil has the old knackered battery,

This is how to do it (says A8 but A6 is the same) - http://wiki.ross-tech.com/wiki/index.php/Audi_A8_(4E)_Battery_Replacement

 

[audiv8quattro]

Why do Audi have to complicate things, I haven't got vag com mate, can't even access the battery meter through my mmi as haven't got that function and there is no hidden menu on mine to activate it lol. But thanks anyway mate, surely after a while the ecu will learn that the new battery is there?