Mchapman

I have a 2011 A6 GS with a GM battery tender (CTEK 3300 except it only has the cigarette lighter connection).

The dealer at delivery left a device on the battery that is for emergency starts if you have a dead battery (push a button for a one time shot at starting the car). Evidently they put these on cars that sit on the lot.....

Anyway the thing is cheap and flimsey and I want to remove it. Will all memory be lost if I disconnect the battery for a few minutes to remove the "device"?

Second question according to the "Motorweek" show on Velocity you can plug in the battery tender through the cigarette lighter and then remove the batter connection and the memory systems on the car will be preserved.

Is this true? Is it safe?

I appreciate any help offered.

Gearhead Jim

You will lose the window indexing if you disconnect the battery, so leave door open or lower your windows an inch before doing that. The re-indexing procedure is in your manual, very easy to do.

Often, the TPMS will show 0 psi on your tires after battery disconnect, just drive for a few minutes and it comes back on.

Using a battery charger with the battery disconnected is said to possibly over-voltage the system and cause damage, so I would avoid it. A battery tender might not have that problem, but still...

The only things you normally lose are the window indexing and TPMS, very easy to "fix" so I don't mess with anything else.

Enjoy that car!

Mchapman

Thanks for the help. I had just never heard of using the battery tender that way. Re-indexing the windows is not hard. Resetting all the personal preferences is a pain but it sounds like they may stay.

Thanks again.

JCtx

I'm pretty sure the tender will disconnect itself like if you had pulled the 12V plug, since it won't detect a battery anymore. But you can try and let us know . Good luck.