A class, reverse polarity problem.

Smudge

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I have just been asked by my neighbour to have a look at his A 160. Seems he has reconnected the battery the wrong way around after charging it ,god knows how!
Any idea's where to start looking. Obviously after connecting correctly it won't start.
 

Alex Crow

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give us a little more info please, do the dash lights work? how about locking? and tell us any thing else that may be diagnostic, like error messages? why was the battery charged, was there preexisting starting problem? suggest you check all the fuses for starters.
 
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Smudge

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No idea as yet going to have a good look tomorrow.
However the central locking is u/s and no dash lights come on.
Car was running fine prior to lights being left on and battery run flat.
All fuses look ok.
 

47p2

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It should not be possible to connect a battery the wrong way. The terminals for + & - are different sizes and the posts are on one side of the battery with leads that would not stretch to the other side.

Did he connect the battery the wrong way or did he attach jump leads the wrong way?
 

television

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A few fuses could have blown,but the damage will probably extensive
 

wireman

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The alternator and any electronics that are permanently supplied will almost certainly be finished.
 

Alex Crow

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good point 47p2, i wonder what really happened......
 
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Smudge

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No idea how he did it.
Just came round afterwards to tell me what had happened.
Looks possible though as I don't think the leads are OEM
 

television

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No idea how he did it.
Just came round afterwards to tell me what had happened.
Looks possible though as I don't think the leads are OEM

Thanks smudge at least it is not your car
 
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Smudge

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Good point Malcolm,hope I am never that stupid.
However I have sold a few EZL units to folks on here who have done just that very same thing.
On the 124's it seems to cook the EZL and alternator.
 

television

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Good point Malcolm,hope I am never that stupid.
However I have sold a few EZL units to folks on here who have done just that very same thing.
On the 124's it seems to cook the EZL and alternator.

For anything that contains a semiconductor it is instant death,, the only saving grace is that they go short circuit,and this could break the chain from the damage going too far
 
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