I need a little help before I go nuts!
I have a 2000 S500 and the cam chain tensioner started leaking. So I diconected the battery and unbolted the alternator and replace the tensioner. Before I put the alternator back on, I decided to run the engine and make sure the leak was gone. connected the battery and started the engine. Test run = A ok. No leaks. shut engine down.
I asked my helper to go to the trunk and disconnect the battery. When he said "ok", I unwrapped the alternator and started to align the brackets and dropped it. That is when I realized he had "not" disconnected the battery. and there was a good arc to ground from the battery lead.
After much choice words, and I disconnected the battery. I mounted the alternator and installed the cerpentine belt. buttoned everything up, and started the engine. The car run great, for about 30 minutes. Then the electrical system started shutting down.
" the battery is NOT being charged "
I have 14.1 volt at the alternator and 12.3 at the battery, slowly draining down until the voltage drops enough to shutdown.
I have 14.1 volts in the fuse block on the passenger side of the engine compartment.
Inside the trunk on the passenger side front area there is a block with 3 red wires and a 4th which ties to the positive on the battery terminal. At this point there is only battery voltages. In the fuse block under the passenger rear seat, there is only battery voltages.
It would seam to me that there is a "fusable link" between the trunk block and the alternator, if so. Where is it located.
Or
what is your best guess.
This is driving me nuts!!!
Thanks
David

 

Could be the fuse block under the passenger floorboard. Also called a prefuse.Certain models have a fuse is that can be replaced there.. sometimes you have to replace the whole prefuse block.. remove the passenger floor board under the dash ..pull that down then there will be a metal floorboard remove that with three 10 millimeter plastic screws. the prefuse block is loc.ated behind that up below dashboard . you will see a large electrical wires running to the pre fuse block. there are fuses located inside that you might have to remove a cover.

 

I passed this info to my buddy, he went into the shop and found the prefuse block, you are referring to. He called and stated it looks similar to the one in the trunk. I have looked on Autohauz and other locations, and can not seem to find one. Do you know what a item number is for this item?
Thanks
David

 

Thanks Chassis221 for the info, you lead me right to the problem.
Upon opening up the Prefuse block, I found a 150amp and a 60amp fuse. These fuses could not be found locally, but upon researching them, I did find they are made by Blue Sea for a marine application. www.bluesea.com , the bluesea stock numbers are 5258 = 150amp and 5253 = 60amp. I ordered them through "Northern Marine" in New Jersey 732-719-2227. Christine had them in my hands the next morning. from Jersy to Tennessee in 15 1/2 hours = W.O.W.! Here are pics of the Prefuse block as it appears and after opening it up.
Hope this can help somone else.

 

You are welcome. glad i could help you.

 

hello I own a s600 with only 66k on miles an 01 she's a beaut..beautiful... however the alternate does not charge the battery and I have replaced both batteries and alternate and checked all pre fuses but I noticed a humming coming from the radio after its shut off. Is that what could be drawing power??? I can't figure it out . My driver tail light lamp stays on as well. I'm lost but the battery does not get charged from the alternate please help .

 

About the tail lamp staying on:
Does your lightswitch point straight up or did you point it all the way to the left?
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