I need to put a trickle charger on an 04 SL500. Which battery should I use? Front (in engine compartment) or rear in Trunk. Any suggestions would be appreciated. Thanks

 

bill...
i have a 03 sl and i put one on both during storage periods..i travel and dont drive it much in winter..
im pretty sure the start battery and the appliance battery (trunk) are isolated when the engine is off.

it has worked fine for me,.

glen