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battery / altenator system

Let me start by saying this is one of the most embarassing things i've ever had to write.  This morning i had to jump start my cougar.  The neighbor that was giving me the jump was in a rush.......so i rushed.    when i connected the cables to my battery i connected them backwards.......then turned around for a second.    when i turned back around smoke was coming from under the cover where the positive cable connects to the solenoid.  neighbors car was fine.    the engine runs fine when connected to a battery thats already charged.  i installed the battery from my truck.  the battery light stays on now.  where do i start with trouble shooting and figuring out what all i fried by doing this extremly stupid thing?  i feel like an extrem loser.  here i am planning for engine swap and learning everything i need to learn......and meanwhile i can't even jump start the car properly.    thanks,  Matt

battery / altenator system

Reply #1 –
Quote from: mattg;316654
Let me start by saying this is one of the most embarassing things i've ever had to write.  This morning i had to jump start my cougar.  The neighbor that was giving me the jump was in a rush.......so i rushed.    when i connected the cables to my battery i connected them backwards.......then turned around for a second.    when i turned back around smoke was coming from under the cover where the positive cable connects to the solenoid.  neighbors car was fine.    the engine runs fine when connected to a battery thats already charged.  i installed the battery from my truck.  the battery light stays on now.  where do i start with trouble shooting and figuring out what all i fried by doing this extremly stupid thing?  i feel like an extrem loser.  here i am planning for engine swap and learning everything i need to learn......and meanwhile i can't even jump start the car properly.    thanks,  Matt

Don't beat yourself up  ..stuff happens,
  I would not be surprised if you ruined the alternator though .
 If everything else is functioning as it should but the light is on that is a pretty good indication that it is no longer charging
 Do you have access to a battery/ alt tester ?
 If not  your local advanpepzone  store should be able to test it for you if you bring it to them :D
Fox-less at the moment

battery / altenator system

Reply #2 –
Diodes are the things damaged by reverse polarity, and the alternator has several of them. The EEC also is vulnerable, but it only had it's keep alive voltage applied since you didn't turn the key on.
Run the KOEO test to see if the EEC can output codes.

I suspect the smoke was "fuse link A" blowing. With the engine off check and see if you have 12v on the BK/O wire at the alternator B+ terminal.

Fuse link A being blown will cause the battery light to stay on and so will blown diodes in the alternator.

battery / altenator system

Reply #3 –
the voltage regulators are not that cheap either.  not as much as a alternator but still, not too short of an alternator cost.

battery / altenator system

Reply #4 –
It's your fuse link,the alternator will be fine.

battery / altenator system

Reply #5 –
i dove into the project today.  The harness with the 3 fusible links attached to the starter solenid was fried.    I fixed / restored the harness with new wire / fusible links.  battery light still on.  checked for voltage at the alternator terminal and nothing.  got new alternator and intalled it.  checked for voltage at the altenator terminal and nothing again.  took it back to autozone.  they tested it and it was bad.  i had them test the replacement before i left and it passed.  Duralast Gold.      That's where i'm at now.  i can't install it tonight cause i have to start cooking for easter.  as always,  thanks for the help!!!

battery / altenator system

Reply #6 –
I put everything back together.  all is well for now.    everything seems to be working fine.  my only concern is i'm getting just under 14 volts at the battery terminals with the engine running instead of a little over 14 like i expected.    I did drive around for quite a while with just about everything turned on, including the AC,  and there were no problems.  Battery had 12 volts with engine off after my long ride with everything turned on.