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D4 - Common Faults Quick links to all known common faults and their solutions

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  #11  
Old 26th September 2016, 07:47 PM
paulrstaylor paulrstaylor is offline
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The more expensive one is an AGM battery, which is used on stop-start cars. If your current one isn't AGM, I'd stick with the standard type
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  #12  
Old 26th September 2016, 08:10 PM
mondie mondie is offline
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The car has start-stop (it's always off though) and I guess has an AGM, all 3 I posted above are AGM although the Varta Silver Dynamic does not promote it. Hence why I am confused, is this all just marketing BS or am I missing something obvious. All of the batterys I have found are slightly smaller in width than the factory battery too.
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  #13  
Old 26th September 2016, 11:43 PM
mondie mondie is offline
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God this is a ball ache.

From tonight's reading, I have found that to code the new battery to the car you need a battery with a BEM code. Guess who sells them, yep Audi and no one else So screw that.

This is what I will buy tomorrow once I have verified the dims one last time, its the closest I can find to what's in the car.

https://www.tayna.co.uk/610-200-Vart...92--P3200.html

Apparently if you don't recode the car after a new battery 2 things can happen.

1) Possibly shorter battery life but this is probably just a scare from Audi.

2) The cars electrics may not function correctly until the car has learnt that the battery is strong. As mine died overnight I assume the ECU has a stored a depleted battery status and the only way for the car to learn it has a new battery is by using the car, starting it over and over etc so it learns and begins to reactivate systems that are shut down to preserve battery power.

Wonder if that's why you experienced issues with your new battery Peter?

Cheers
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  #14  
Old 26th September 2016, 11:52 PM
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briang9 briang9 is offline
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Not sure if your car is the same, but I recently replaced the battery on my RS6 with a non OEM battery, a YUASA one actually. When recoding in the new battery my mechanic was able to use the details of the old OEM battery which it happily accepted, seems as long as it knows it has a new battery it's happy, hope yours is as easy
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Last edited by briang9; 27th September 2016 at 12:13 AM.
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  #15  
Old 27th September 2016, 12:21 AM
mondie mondie is offline
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Brian, yes I read that any details will do provided you can get the car to accept them. Seems like its a load of tosh, resetting the ECU/BCM so it knows it has a new battery is what matters I gather. I guess I will see how I get on without this in a couple of days.
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  #16  
Old 27th September 2016, 08:47 AM
paulrstaylor paulrstaylor is offline
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Quote:
Originally Posted by mondie View Post
2) The cars electrics may not function correctly until the car has learnt that the battery is strong. As mine died overnight I assume the ECU has a stored a depleted battery status and the only way for the car to learn it has a new battery is by using the car, starting it over and over etc so it learns and begins to reactivate systems that are shut down to preserve battery power.

Wonder if that's why you experienced issues with your new battery P̶e̶t̶e̶r̶ Paul?
Exactly that, and that was six months after changing the battery! Net result was things just acted weirdly and the car went into "hibernate" mode far too often. New BCM and new battery and they are hopeful it will be resolved.

Have a read of http://wiki.ross-tech.com/wiki/index...ry_Replacement, the "trick" on the D3 was to use the old battery data but to change the last number of the serial number for the BCM thinks it is actually a "genuine" new battery, not sure if that will work with the D4 though!?

In any case, good luck
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  #17  
Old 27th September 2016, 09:41 AM
mondie mondie is offline
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six months and still a problem! Hopefully the BCM was the cause of this but what are we coming to when you cannot safely jump a car and need to spend hours learning how to change a battery. Its madness.

If I can get the car going then I will be happy as I can have the car reprogrammed by an Audi specialist next month.

Cheers
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  #18  
Old 28th September 2016, 10:32 PM
mondie mondie is offline
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The new battery arrived today from Tanya, 99 delivered. This one:

https://www.tayna.co.uk/610-200-Vart...92--P3200.html

Fitted it up no problem, case was identical size/shape to the OEM and ratings all within a few percent too. Car started and runs normally, all electrics work normally too, its as though nothing ever happened. So far so good

Thanks for all the advice on this thread.
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