Like the title says, the battery indicator light is on in my dash. It shows a pic if a battery and says visit workshop (in red). Strange thing is that it shows up in the morning when i start the car, but when i shut it off after a quick trip, the indicator goes away and shows no malfunction I know these cars have two batteries but which turns on the light is a mystery to me...help please.

 

When was the main battery last changed? My battery did the same thing and a new battery fixed the problem.

 

do you have the car parked for long periods at a time???

 

my car started doing the same exact thing couple weeks ago...

 

about a 1-1 1/2 weeks at a time..

 

and this is exactly why I was checking the forum today. My car started doing it on saturday and after a short drive, the indicator did not come up again. I started it monday morning, and it came up again. I also only use the car during weekends, and it might be parked for one or two weeks without use. I was thinking that this might be related to the auxiliary battery, and not the main one, but I will put a battery tender on the car and see if it goes away. FWIW both times the indicator came on, the car started fine.
Best regards
Victor

 

I have heard that 2-3 weeks of sitting is enough to run our batteries down to the point where they won't even start the car. Apparantly there is quite a parasitic draw when the car is parked. It is also my belief(completely unfounded of course) that many of the issues E55 owners report are due to the length of time their cars sit without being driven. I think a battery tender will certainly work for you in this case. If the problem persists with a tender, then it's new battery time.

 

Had the same problem. I replaced the main battery in the trunk and warning light was still on. Car went back to dealership, they determined the problem was a bad battery charging circuit board. Cost of repair was $1162 canadian including taxes.

 

i'm thinking that the battery is just week(not dead,still enough cold cranking amps) after sitting for that time. So when you start it and run it, even though the alternator is charging it, it is still throwing these warnings... Which explains the following....

after the alternator has completely charged the battery the warnings will go away...

IMHO if you take it into the dealer, they will tell you that you need a battery, but that is not the case here... I had the same problem as you before i drove the car from Florida to New York.... Red warning battery light.....Started the car after almost two weeks of sitting, I hit the road and car to NY and problem has never returned...

If you have a multimter tester do a battery and a alternator test....

 

i drive my car just about every day and that warning will only come up in the morning. after i drive for a couple miles turn the car off and drive elsewhere the warning will not come on.

 

After 3 batteries, I got tired of the BS. The battery would run down even before I put in all the stereo equipment...this was after 2 weeks of just sitting around.

I eventually bought a trickle charger for the main battery in the back and then another trickle charger for the auxillary battery in the engine compartment (left side close to firewall) and hook them up whenever I know I won't be driving the car much...

MB sells them but you can get the same one (CTEK) off Ebay or Amazon for a lot less...you can practically get two for the price of one that MB sells.

The only difference in charging the main battery with the aux battery is that the auxillary battery is considered similar to charging a bike battery and there is an option on the CTEK for bike batteries.

No problem at all now...those two investments has saved me a couple of batteries and a lot of wasted time and energy.

 

Ctek is a good charger. I have "Battery Tender Plus" Its pretty much the same as Ctek. I use it on both cars and bikes.

http://batterytender.com/product_inf...2e3b32eafc8ee1

 

mine too...only in the morning. So whats the concensus? The battery, aux battery, charging circuit, or alternator?

 

I highly doubt the alternator, or the battery warning would never come off....

 

+1. if the alternator was bad then the bettery light would not turn off, or the charging circuit at that since it wouldn't charge the battery ( i would think). since even after a week of sitting my car starts fine, i am thinking that it may be the auxilary battery in my case.

 

Makes sense, my car starts fine also. Guess its the aux battery or main battery. If u guys figure it out, let me know...ill b outta town but ill be checking the board.

 

Just dropped off the car for this exact thing. The manual says it could be the belt that drives the alternator, but SA says highly unlikely. SA said it could be battery to alternator or anything involved with the charging even the computer. My light also went on and off and after doing a search and read about cars dying on the side of the road, I thought I should bring it in right away. I'll update when I get the car back.

 

Turned out to be the accessory battery, I believe that's the smaller one up front, wasn't charging correctly. They said the other battery, alternator, electronics all checked out okay.

 

I recently had a flat tire and had to call TeleAid to have a tech come out to change the flat for me (it was 11:00 PM and I had no source of light and I could not see where the jack would fit). Anyway, the tech and I had a pretty good conversation about many aspects of MB maintenance and what to go to a dealer for and what not to go to a dealer for... (example, he stated that paying $50.00 at the dealer for a tire patch simply is not worth the money as they do nothing different than a tire place would do and that the nitrogen they put in the tires is more or less a gimmick). He also told me that if your battery does go dead, not to buy it from the dealer, but to call them, as they will only charge you for the cost of the battery and not for maintenance/markup (he stated that the roadside service was a Mercedes Benz of North America program, not a dealer program). He also told me about my car having two batteries (which I did not know at the time). He stated that if it was the starter battery, they usually don't carry them on their tech vehicles; however, if I called him directly, he would be able to go to the dealer and get it for me before he came out. He also stated that the battery display on the dash can display two colors. Yellow for the starter batter and red for the main battery (I may have this backwards)... Just thought I would add this info...

 

Where is the aux battery located?

 

All I know is it is under the hood. I didn't know about it, so I never looked for it...

 

under the hood. passenger side, closer to fitewall, under plastic cover.

 

+1...it has one plastic screw that keeps the cover in place.

 

I had the red light on. I read some had a faulty alternator that caused the light to go on.

 

ok...so its the aux battery then...any where else to pick it up besides the dealer?