Racerxjling

Not sure if this has been discussed but thought I would help out others if it hasn't. If you get the message in the title (red color), there are 2 batteries in the car (I have a 2006 E55). One is the regular larger battery to start the car (in the rear) and a smaller motorcycle size battery located in the front passenger side UNDER the cabin filter by the firewall. Since I wasn't having any starting issues I changed out the smaller battery and the warning light disappeared. MB service guy said this is the battery that powers the dynamic seats and other electronics in the car. It's an easy DIY job w/ a 10mm deep socket for the entire job.

Jeff

E55Pilot

It's the battery that powers the SBC

NSX2NV

It also power the accessories like heated seats, etc.

theeddie

go to autozone get a battery for a sea-doo its about $69

takes bout 15 min to swap

Racerxjling

Damn, celebrated prematurely. The battery icon light came back on!! Since I am not having any starting issues at all I didn't think it was the big battery...maybe a dead cell?? Does anyone know if there is a need to "reset" the light? It also doesn't come on all the time. This leads me to believe I may have one dead cell or a partially dead cell in the large battery now.

Jeff

Marcus Frost

Jeff,

The small battery in the front of the car is the starter battery that also powers a few functions such as ones required on startup. The main battery in the trunk is still the primary battery that the car uses when in operation. It is likely your primary battery needs replacing.

-m

Racerxjling

Hmm, the service advisor at MB said the small battery in the front is not for starting but for the electronics in the car. It does seem too small to be used as a starter battery. Are you sure? Guess I will do a search on what you guys are using for the main battery. I don't even want to get a quote from MB on the cost of the main battery. Thanks for your help.

Jeff

Friction

Just recently went throught the battery warnings only to have the car completely freak out and die. Turned out it was the alternator. I had the dash warnings as you described, only not in red, and was on the way to replace the big battery in the trunk when the car totally died about 200yards from the dealer. FYI, when the batteries both drain, you loose all power options in the car INCLUDING BRAKES. Remember that your accelerator and brake pedals are electronic, not mechanical.

NSX2NV

Yes you are correct. That happened to my friends E55 on our way to Saint Louis. He had to get it towed to the dealership and I think it ended up costing him either almost 2 grand or maybe even a little more. Best of luck on yours man. If I were you I would buy the parts myself online. That should save you some cash. Maybe find a salvaged E55 and take the parts off that. Good luck!

Racerxjling

Are you saying that the brakes would fail when the battery fails? I can't see how the engineers would design it that way unless they did it during Oktoberfest.

Jeff

NSX2NV

Yes the brakes fail! I was in the car when they did in my friends car. We were pulling off the highway and he said the pedal went to the floor for a second before the brakes engaged. That's when he realized he shouldn't have been ignoring the RED screen saying "Battery Visit Workshop"

Racerxjling

Wow, better just change out the big battery as well. Think it's ok to go w/ an Autozone battery for $130 (Duralast gold)?? Or, shoud I check w/ Costco?

Thx

Jeff

NSX2NV

I don't see why not as long as it is the correct amperage and size. I don't think the computer is going to be able to tell a difference. If command says get this Duralast Battery out of here I'll give you my battery

Ted Baldwin

...........It is ABSOLUTELY your alternator!! NSX2NV is completely correct. You are about to get stranded in the middle of the road. Trust me on this one. Get into you car and drive DIRECTLY TO THE SHOP. So long as your car cranks up, you do not need to change the battery. You can change the battery if you like, but every second you spend debating about the battery pulls you closer and closer to getting stranded on the road. The car WILL freak out and will totally die without warning, even if you are in the middle of the highway. YOU WILL NOT HAVE TIME TO PULL OVER!!! REPEAT, YOU WILL NOT HAVE TIME TO PULL OVER!!!

Ted

Racerxjling

OK, will have the alternator tested. The light has been on for the last 3 months but has been sporadic...maybe on about 75% of the time. Will get it tested and let the board know. Man, if it's the alternator it didn't last long as the car has 55k miles. NSX2NV and I are not used to this (I have a NSX as well) in the NSX!!

Jeff

NSX2NV

I know aren't they great! I love them!
This is my first ever owned.

This is my Comptech SC one.



But never forget the Beast E55!

Ted Baldwin

.......my car was 40,000 miles when it happened. I drove 600 miles from the initial warning till the time the car died in rhe middle of I-95 between FL and GA. Apparently the cars are engineered to give you fair warning. It is really scary when the car eventually dies all the christmas trees will light up and in less than a minute, the car will TOTALLY die. Yes, i did chane my main battery after i got the warning light. It was not the battery. Thw warning light came back. I thought at the time that the ECU just needed to reset. Wong! So, take no comfort in the fact that your car has 50,000 miles or that the warning light has been on for 3 months.

Ted

Racerxjling

NSX2NV-Very nice rides!! I've also owned 2 NSXs..no pics of the first but here is a link to the story of my 2nd & current one. I am redoing the entire audio system on it now...will be ready by the end of the week.

http://www.nsxprime.com/forums/showt...ight=02+update

The E55 is actually my bro's...I've been working on it to help him out w/ his busy schedule. I love the car though. I have an 03' M5...I know the dark side for you MB guys Both cars are awesome IMO.

Jeff

Racerxjling

Thanks Ted! Since the car is 3 years old. I think I may change the battery anyway (any quick tips on which one other than oem?) and of course test the alternator at the same time. Will keep you posted.

Thanks!!

Jeff

Racerxjling

Ted, I forgot to ask you if you went w/ a MB oem replacement alternator (ouch! not going oem...just checked online at it's over $800!!) or did you go aftermarket/rebuild oem?

Thx

Jeff

Racerxjling

OK, went to Autozone this a.m. They load tested the big battery in the trunk and "battery good". They also tested the alternator and it showed 14.0Volts. So, don't know what to do from here. Battery icon light didn't go on while I drove it there nor back (5.0 miles roundtrip)/.

Jeff

NSX2NV

Nice NSX! I love the 02+ headlights.

Racerxjling

Thanks!! The very last pic in the end is how it looks now. Goal was to be unique (rare larger Ctech SC, CF wheels, and custom one off AMG front brakes) on the main parts. The audio setup will be unique as well..will post pics in a week or so...can't wait.

Jeff

Icandr55

Racer, had similar problem. When I got my Kleeman stage 2 installed, they hooked the intercooler pump up directly to the little battery in the front which by the way has nothing to do with starting. It does run SBC and some electronics as mentioned. Anyway, they did this so the pump would be always on, not just when the supercharger engaged. It ultimately kept draining the small battery. The same warning light you have would intermittently come on and then stay on when the battery totally failed. Later, even after replacing the small battery, the light would stay on. The problem was this battery's control module or relay that controls flow to recharge this battery burned out because it is basically a gate to direct flow to recharge the battery and the small battery was asking to be recharged constantly. The ecu detects when this relay fails and also gives you the red battery light warning. Perhaps your relay is out? If it is everything still works,but the light is always on.

Racerxjling

Thanks for the input. My bro said the light hasn't been on for 2 days so we'll see. Maybe it took a day to recharge the battery that I installed. I expected it to be somewhat charged from MB. If the light returns then I will maybe replace the relay/control module. Do you have a part # for it per chance? Thanks!!

Jeff