Did I blow my engine electrics?
 

So I come home from Georgia,
Find that my father bought a new battery for my car,
Thats very nice of him,
Why did he buy one you ask?

He says old one was four years old and was not taking a charge anymore,
So I installed this new battery and tried to start it,
but the car did not start, instead... this is what happened:

1. Key turned to second position, all dash board lights turn on, buzzer goes burrrrrrrrrreeeerrrrrrr like normal,

2. Key turned to start position,
small popping noise, then everything stops working,

what have you done, I angrily ask him, but I know he knows no better,

I put the key in today, turned it to position two, only one light came one, the red SRS but it was flickering and the buzzer was going in and out,
Even with the battery connected, there are no power locks, no radio, NOTHING,

I open the hood to find that he installed an 810AMP BATTERY!! DEAR GOD!!!!

Please note that my car has the updated OVP relay.... I will be going to Costco to return the battery...

Questions to the wise people of the board:
1. How bad is it? ECU? OVP? I checked the fuse box, nothing blown there, have not checked OVP yet. Other stupid crap keeps taking my time!
2. What kind of battery do I need for this car? This one that I have does not even fit the tray properly....

If this car is destroyed, I will lose my job starting January!!! WAAHHH!!!!!!!!!!:(:(:(:(:(:(:(

Make sure you battery terminal are tight, I usually use a pair of channel locks to try to wiggle them. MY VW's stock terminals tighten down with a 10mm wrench, but the actual electrical connections aren't tight. I usually clean them with a wire brush, and spray them with the red anti-corrosion spray. I know (from the pissed off phone calls from a stranded wife) that a loose connection can cause all kinds of wired symptoms. Car will just click and all dash lights go out, car will start to crank and them stop with a CEL light. Good Luck, Chuck

810 amp rating is good ...
 

that is the amount of current the battery can produce if called upon - like a cold, cold morning when the motor oil is stiff. It's excess voltage that would be harmful to electronics but a battery by itself won't produce that. It can only produce up to about 13.5 volts. A bad voltage regulator would allow the alternator to appy an unsafe voltage to both the electronics and to the battery. This can boil the liquid in the battery and ruin it as well as make a real mess in the car.

yeah what is that CCA? as long as it's a 12v battery, you're not in any danger. Check/clean the battery terminals- also since you said it doesn't fit well, make sure the battery post isn't coming in contact with the hood.

Hello everyone, thank you for replies.

I got to Costco today, returned the beast of the battery and got a new one.

This new one has
735 cranking amps at 32 degrees celsius,
590 when cold,
The reference book that was there said that the original equipment cold crank amperage was 550. (1986 to 1992 300E)

I understand now that the higher the amperage, the more power to start.
Of course, I bought 12V batteries as the car is based on 12V.

Well I installed the battery, which fit depth and length wise, but damn did Mercedes use a very very wide battery originally. I wonder where you could find a battery that fits the tray in entirety? I am guessing the white box Mercedes-Benz battery?

Anyways, engine fired up within 1.5 seconds of crank.... I love this car! :kid:

I wonder what was wrong with the first battery, obviously, as I have learned, higher amperage is really only a good thing... I noticed that my first battery was manufactured on 9/2007 and the second one on 12/2007. Do car batteries have short self lives or did I just get a dud? I made sure that the posts did not contact to hood of the car, so that was not it.

Sounds like Dad's battery was not charged.

I agree with Earl - sounds like the 810 wasn't charged. Too bad..I would've preferred that one, if I lived in the great white north. Atlanta isn't so bad, so the battery you have now ought to be fine.

I wondered about the large battery tray too and concluded that Mercedes used the same tray for gas and diesel cars.

Your dad did you a big favour and bought you a very good battery. Make sure you thank him properly!

Actually, the OEM Mercedes battery is decently priced at the dealership...and you can have the confidence knowing that it's the correct battery, with the correct dimensions and terminal orientation.

The other alternative is Interstate Battery...their alternatives match the OEM offerings (including the weird trunk mounted units required for the SL and CLK)...and they are cheaper than the dealer.

Thats exactly it. They share the same tray but use different clamps to hold it in place. My diesel 124 takes the large battery.

The PO of my car put in an Optima Yellow Top. Nice battery. Too bad the PO also lost the hold down, so now I just run it redneck style with a ratchet strap across the top. :D :)

Battery
 

You will need a 88Ah battery normally 354x174x190mm will fit :)

Maybe the batter was in BACKWARDS......

Hey! I may not be the brightest bulb on the Christmas light string, but I know how to properly hook up a battery! :(

I thought you said your dad replaced the battery, none the less, IT HAS HAPPENED to some MB owners with similar problems.