Auxiliary battery

[ShaunB]

Guys

What does the auxiliary battery actually control on the cars
Mine is a CLK55 - 2004MY

I'm having a weird issue with the automatic window dropping when you open the door.
I'm pretty sure this battery has never been changed, given I replaced the main battery earlier in the year which was still the original unit.

Cheers

 

[whitenemesis]

I had no idea the CLK was ever fitted with the dual battery system. The aux battery in models that do have it simply support the main system battery. The exception being the SL where the smaller engine bay battery fed the starter only.

 

[dozypillock]

I had no idea the CLK was ever fitted with the dual battery system. The aux battery in models that do have it simply support the main system battery. The exception being the SL where the smaller engine bay battery fed the starter only.

Does anybody know if the C209 has a second battery? Never really taken anything apart in the rear of the car yet. Seem to recall the data card said High capacity battery, so assumed it only has the one.

Neil

 

[ShaunB]

I just assumed there is a secondary battery, because when the battery died the radio stations on command remained as I had preset them to.

 

[whitenemesis]

The C209 does not have a dual battery system.

Only the W211, W219, R230, Maybach and SLR did and the first two only up to 2006.

Unless someone knows of others?

 

[whitenemesis]

I just assumed there is a secondary battery, because when the battery died the radio stations on command remained as I had preset them to.

Comand has its own memory backup battery, similar to that in a PC

 

[ShaunB]

Fair enough - thank you very much

 

[Will]

Yep - pretty sure there's only the one battery on CLK models. Even my 208 CLK used to keep the memory for the COMAND, but you'll lose the one-touch function for the windows etc when the battery is disconnected.

 

[dozypillock]

Comand has its own memory backup battery, similar to that in a PC

As mine is now 12 years old, is the battery in the comand replaceable?
i.e is it one of those flat C2032 or whatever type batteries?
If its like the PC type ones, I doubt it still works?
I do not know when my Main battery was last replaced, so assume it may let me down soon, so would rather pre-empt it, and sort it now.

Neil

 

[richard]

ShaunB

What is your weird issue with the window dropping as you open the door? It should do that (so should passenger door) to drop the glass out of the door seal. After you change the battery you will probably have to resync the windows so the 1-toiuch works again and I suspect for that function to work properly as-well.

Richard

 

[ShaunB]

Hi Richard
Basically the passenger window doesn't seem to drop enough, and catches the seal as you close the door.
Its only out by a few mm, and doesn't catch the seal all of the time, but in fairness its does catch it most of the time.
More annoying than anything else really.