Dead Battery Problem
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Super Member
Joined: Jul 2005
Posts: 831
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From: Denver,CO USA
"88 300CE- First Year Production
Dead Battery Problem
Now that this have happened more than once I have noticed that if I drive for about 30-45minutes with both my sound system and the air conditioning on that my battery pretty much dies and jumping the car fixes the problem. What do I need to do to fix or avoid this from keep happening? It did it today with only a weak kenwood 300rms amp, and the a/c blowing cold, and funny to say both times I had it blowing cold. Do I need a new battery and amp or what am I to do?
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Joined: Jul 2005
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From: Boston
is a German Tank
Now that this have happened more than once I have noticed that if I drive for about 30-45minutes with both my sound system and the air conditioning on that my battery pretty much dies and jumping the car fixes the problem. What do I need to do to fix or avoid this from keep happening? It did it today with only a weak kenwood 300rms amp, and the a/c blowing cold, and funny to say both times I had it blowing cold. Do I need a new battery and amp or what am I to do?
Are you sure its not your alternator??
Try starting the car and while its running disconnect the battery cables.
if your car dies when you disconnect the cables then you are in need of a new alternator.
Thread Starter
Super Member
Joined: Jul 2005
Posts: 831
Likes: 1
From: Denver,CO USA
"88 300CE- First Year Production
I'm not sure what I need, Thats why I posted, most likely its the original alternator from '88. I think its the alternator myself, so who sell the bell higher amp alternators for our cars?
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they were upgraded at some point, i think about 90. so if you do buy a new one its gonna be the upgraded one anyway.
first check out your battery though. check water level, test it (most auto stores will do it for free.) then have it charged. a long slow charge is better than the quick two hour pep boys special. make sure you use distilled water to fill it up.
if the problem isnt your battery, it could still be something other than your alternator. i had charging problems last year that turned out to be the overvoltage relay.
first check out your battery though. check water level, test it (most auto stores will do it for free.) then have it charged. a long slow charge is better than the quick two hour pep boys special. make sure you use distilled water to fill it up.
if the problem isnt your battery, it could still be something other than your alternator. i had charging problems last year that turned out to be the overvoltage relay.
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Joined: Apr 2005
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From: Northern Cali
W124
If you're gonna test your alternator by removing the connections don't reconnect them until the car is off. You can short out the ECU if you try to reconnect the battery while the car is still running.
