Disconnected battery and car in 'safe' mode?

[AudiSport]

Hi all,


I have a 55 Audi A4 2.0T with a stage 1 Revo map. It has had an intermittent problem where my built in Bluetooth hands-free would get stuck on call mode. However I could turn my iPhone Bluetooth off and clear the problem. This week, once again it got stuck on CALL. However nothing worked this time and when I came out from work my car only just started as it was obviously draining the battery. So, when I got home I disconnected the battery for ten minutes and once reconnected it has finally cleared.


However, it's still not right. And to make it worse my car seems to have gone into some safe mode. It's very slow, slower than standard and seems to be restricted?

 

[Craig Cull]

My battery died last week and had to replace it. The loss of power was so noticeable I nearly sold it lol. It will sort its self out over a few miles. (someone on here kindly advised me of this). But I also plugged mine in and reset the fault codes. Think it's around 25 miles before it will sort its self out. But I understand, the loss of power is unreal and mine isn't even mapped, also fuel economy seems to be poor. If it doesn't sort it's self out, get it plugged in as it may still be logging a fault code form the disconnect

 

[AudiSport]

Thank you for the reply. The strange thing is that prior to me unplugging the battery the car was running fine, so I suspect it's a little more complicated ; (

 

[audicruiser]

Thank you for the reply. The strange thing is that prior to me unplugging the battery the car was running fine, so I suspect it's a little more complicated ; (

No it's because you disconnected the battery. When you do this it resets everything and so the engine feels flat and underpowered until everything readapts again.... As said this will take upto 50 miles or so.

 

[Craig Cull]

Mine was also running perfect before the battery died. Just been to the coast Init today and it's totally bk to normal.

 

[AudiSport]

Ah, new battery or should I just keep driving for a while? The car is so slow, it's in like 'safe' mode!

 

[Craig Cull]

Keep drivin mate, apparently takes about 30 miles to pick up the info it needs to run properly.

If you hae done more than 30 miles and uve seen no improvement, mite be worth getting someone to plug it in and make sure there's no other faults

 

[AudiSport]

Well today it seemed to improve - but as I only do 8-miles a day this could take a while!

 

[NHN]

Well tbh there are a few possibles, but there are known issues of BT units that can drain the battery, I would get the battery properly charged with something like a ctek charger, leave it to do its thing, the 8 step versions are fantastic & great value, then try the car for a few days see if the issues repeat, if they do, then try disconnecting the BT unit, charge the battery up again fully with ctek & see if issues return, that way can see if its BT or just an old battery on last legs, as your sig shows an 05 car, battery is also a possible tbh.

 

[k1ano]

No it's because you disconnected the battery. When you do this it resets everything and so the engine feels flat and underpowered until everything readapts again.... As said this will take upto 50 miles or so.

This has happened to me twice in recent weeks due to me flattening the battery by leaving the interior light on ... the re-adaption feels pretty unusual as the car behaviour noticeably changes and then gradually improves

Martin

 

[AudiSport]

Changed the battery which made no difference, however the car was serviced last week and they fixed it by resetting the Revo remap. So, all good again! ; )

 

[NHN]

Huh, revo remap reset cures this issue, how is that even related whatsoever.

 

[Jeeves]

Huh, revo remap reset cures this issue, how is that even related whatsoever.

Maybe they took it for a bit of a drive

 

[NHN]

That doesnt cure a battery drain issue, just prelongs the inevitable.

 

[hades-]

who reset the revo ?

 

[AudiSport]

The garage who serviced the car reset the Revo. They also happen to be the Local Revo installer, and know there stuff. When I disconnected the battery is put the Revo into a very slow setting. It may have even been one of the setting pre-programmed with the switch I've got. Not sure why this happened, but thought I'd update this post for future reference.

 

[NHN]

Ok, that shouldnt happen with revo afaik, my 1st map was a revo on my S3 8L & never once had the same issues, that was sometime back of course, but to lose power because of a battery disconnect is concerning.

 

[AudiSport]

Ok, that shouldnt happen with revo afaik, my 1st map was a revo on my S3 8L & never once had the same issues, that was sometime back of course, but to lose power because of a battery disconnect is concerning.

I was told this always happens with the 2.0T engine, however not on others.