R350 alternator
 

My battery picture service message comes on telling me to visit workshop. I took the battery to the parts store (its 1 1/2 years old) and they told me it was good. I put it back and took it to the parts shop and they said the alternator at idol generated 46 volts and that it was good. They said the battery was bad. How many volts should the alternator be charging when at idol? It is a 2006. thanks

At idle, an alternator can charge up to about 85A on that model when requested.

Have you checked the "little" secondary battery? Many cars had a service campaign on that battery.

Little battery
 

I didn't know there was one. Where is it located?

Depending on your VIN and which fault codes you've got, there are a couple of repair solutions that may apply to you problem. :confused:

Answer
 

Battery
MB# 000000004039

It is in the battery compartment under the rear of the passenger side front seat.
You have to move the passenger front seat all the way forward.

* You may find it easier to remove door moldings.
* Pull up the carpet to gain access to and remove the actual fiberglass panel/false floor.

Make sure that the battery is being charged, they do go bad but some fail because the front SAM stops charging them..
Easy test is to monitor it with a meter and make sure you see 12v at some point.

Warning: If for any reason you unplug the yellow SRS connector under the seat while there is live power it will set a code, that will require SDS (Star Diagnostic System) to clear.

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r350 auxilary battery
 

Alright. Now I'm confused. I only see one battery and it is under the passenger side seat. Where is the other one, it's not under the hood.

Hmm
 

Item 14 in the picture, it hides in a floor pocket/trap door.

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