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Discussion Starter #1
Just wondered if anyone has aany knowledge of a scenario like this. I was driving down the road the other day and my CD player cut out for a second. It was nighttime , everything continued to work until I shut the car off. It would not start after an hour of sitting. Replaced the battery not knowing how long the old one had been there and this did the trick for a couple of days. Tonight on my drive home, the CD player again clicked off. Now the car doesn't seem to have enough juice to start. The only thing that has changed is I recently added an amplifier to the stereo. I was reading a couple of earlier posts about the alternator only having an about 5 extra amps to charge the battery. If anyone has any insight, please help...
Thanks.
 

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Take a look at the charging system. It sounds like it's not charging. If you find it's ...

Take a look at the charging system. It sounds like it's not charging or your amplifier draws too much. With a volt meter, you can find the problem. If you find it's not charging,and the radio is off,(cause the amp will not draw if volume is down), before you accuse the alternator or regulator assembly,unplug the bigger of the two plugs from the glow plug relay. They do stick and take all the alternator has to give. If it charges with the big plug off, get a new timer control. If it does not charge with the plug off, repair alternator as required....
 

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Do you know how much power the amplifier is rated at? The stock Bosch alternator is onl...

Do you know how much power the amplifier is rated at? The stock Bosch alternator is only rated at 55 amps. If the amplifier is really powerful then chances are that the alternator is having trouble keeping the battery charged, and indirectly powering the amplifier. The alternator charges the battery, and then the amplifier gets its immediate power from the battery. So, the juice that the amplifier draws may be preventing the battery from being able to keep its charge, leaving you with a dead battery.
 

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Discussion Starter #4
Thanks fellas,
Will try both suggestions and let you know.

...


Thanks fellas,
Will try both suggestions and let you know.
 

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Discussion Starter #5
No thing on the MB side

Disconnected the amp just to see if she'd keep a charge. No problem whatsoever after. Its a sign. The only thing the amp and sub did was make other people aware that I had a stereo. It was more audible outside than inside. Through the gas tank/steel/ seats I could feel it in my feet but never properly hear it. What are those of you who've put a sub in your first aid kit pushing it with? Thanks for the help...
 

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Have you tried to see if you can hear the sub(s) better if you take out the first aid ki...

Have you tried to see if you can hear the sub(s) better if you take out the first aid kit? Because it's basically a hole from the cabin through the rear deck into the trunk that you can stick your arm through. Or maybe it's too small of a passage?
 

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Forgot to mention to make sure the glow plug relay is not sticking. If it sticks it will...

Forgot to mention to make sure the glow plug relay is not sticking. If it sticks it will draw MORE than the alt can supply.........
 

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Discussion Starter #8
Still dead

So After completely removing my amp etc, I continue to have the same problem. I swapped out the glow plug relay/timer with one I know is working from a friends car and no luck. The interesting thing is once the car is started I can run the lights/radio/ wipers etc no problem. I measured the voltage on my battery to see what it was getting and it matched my friend's exactly. I am extremely confused. What is the proper way to test the output of the alt and/or could it be something simple I am missing? Any and all responses appreciated as the car runs wonderful after I get it started.
Thanks

r*
 

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Re: Still dead

So After completely removing my amp etc, I continue to have the same problem. I swapped out the glow plug relay/timer with one I know is working from a friends car and no luck. The interesting thing is once the car is started I can run the lights/radio/ wipers etc no problem. I measured the voltage on my battery to see what it was getting and it matched my friend's exactly. I am extremely confused. What is the proper way to test the output of the alt and/or could it be something simple I am missing? Any and all responses appreciated as the car runs wonderful after I get it started.
Thanks

r*
so what is the voltage?????
 

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Discussion Starter #10
Readings

I was getting 28 but I am not sure this is accurate. It was the same on my friends TD and her charging system appears fine
 

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1991 300 SE
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The same problem...

I had a problem with a new battery where after replacing the battery the car would start a few times and then would not start. My mechanic charged the battery overnight and its worked fine since. The new battery came off the shelf undercharged and the car’s charging system can not charge an undercharged battery, it can only “top off� the battery after it starts the car.

With that in mind is your battery holding a charge after several days? You’re having the same problem in that the car looses power and you can’t get it started? How are you getting the car started after the problem returns? Have you checked for worn/exposed wires or cables causing the battery to drain or not charge?

Hang in there, we’ll figure it out!
 

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another possibility is that there is an aberrant circuit somewhere in your electricals t...

another possibility is that there is an aberrant circuit somewhere in your electricals that basically short-circuits your wiring and drains your battery even if your car is off. this may have nothing to do with your new sound system (coincidence) or it's possible that some wiring got damaged when they performed the installation. it should be pretty easy to check the circuitry for any voltage draws with the proper equipment.
 

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Re: Readings

I was getting 28 but I am not sure this is accurate. It was the same on my friends TD and her charging system appears fine
Better check it again. If you have 28 you have enough for 2 cars! Use an accurate digital guage....
 

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Discussion Starter #14
13.2

13.2 V when the car is running. When the cars is off the battery is approx 11.6. The other 2 MB's I checked were well above 12. Can this be because the battery is dead/near dead or do you think its because I got a bad battery. I'll have it checked. Holidays....
 

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Discussion Starter #15
Bad Battery

The new battery was bad. Seems the simplest things slip past you when you rely on the quality control of parts manufacturers. Hopefully this clears everything up and I didn't have to spend a bundle...
[:D]

Thanks for all the help guys.
 

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Discussion Starter #16
Dead Again

Well she lasted 6 days this time. wahoo. I noticed when looking under the hood that some radiator fluid may be dripping onto the alternator but the auto parts guy assures me an alternator is either good or not good and as I have posted before when she is running she runs with lights, heat, radio, wipers etc. Anyone know if this is true(alternator good or not good)? Sorry to be the newbie, elctrical issues have never been my strong suit. And at this point its me vs. her as I have a couple days to work with the problem. I am also hesitant to take her in as replacing both the relay and the alternator would probably be as expensive as garage labor and fixing the problem... Piece of mind? Not sure. Any insight greatly appreciated.
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The bad battery is dead again, or its replacement? You can get your alternator checked ...

The bad battery is dead again, or its replacement? You can get your alternator checked for free at AutoZone and I think PepBoys and some other similar auto parts stores (e.g.- I just saw a commercial the other day that another auto parts store has started doing free checks, it may have been Advance Auto Parts or Discount Auto Parts or some similar-sounding chain). But if you can get to an AutoZone they'll do it.
 

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If your battery has lasted six days then I’d say your alt is OK, the battery would be dead by now if your alt was bad. Yes, have the battery and alt checked, one would hope for free, as noted above. (we feel your pain $$$$$$)

BTW, have that leaking coolant checked, even if it does not hurt the alt (?) it can’t be good. Sounds like the lower radiator hose.
 

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Discussion Starter #19
Okay call me an idiot but it was the alternator belt. Apparently it was not tight enough giving me just enough juice to keep going for awhile. The bad battery thing had me way thrown off as well. Sometimes we overlook the simplest things thinking the worst. Thanks everyone for the help. I now know my charging system to a tee. So that's good news.
Cheers
[8D]
 
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how did you figure it out that it was a bad belt ?
did someone tell you about it or you just saw it ?


just curious....
 
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