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Electrical Failure After Battery Change

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#1 chris-vxt



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Posted 29 October 2019 - 04:35 PM

Hi, I’ve just changed my main battery and the little back up battery.
What a pig!!

After the job I got in all pleased with my efforts and turned on the ignition which was all fine, everything lit up as expected. When I pressed the start button everything died.

Does anyone know what this is likely to be? I’m not very good at auto electrics so after some pointers of where to look tomorrow when I take a better look.

Also is there a main fuse to replace? The whole dash went dead so I guess that’s more that a regular blade fuse but again, any help appreciated.

It’s a 2003 VXT if that makes any difference.



#2 fiveoclock


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Posted 29 October 2019 - 05:59 PM

Have you checked the battery connections

#3 Zoobeef


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Posted 29 October 2019 - 06:22 PM

As Mark says, battery connections is the obvious thing. 

#4 fiveoclock


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Posted 29 October 2019 - 06:40 PM

All can seem ok when you turn the ignition but when you try and start it the extra current draw can "throw" the clamp off the terminal enough for it to go dead

#5 siztenboots



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Posted 30 October 2019 - 11:45 AM

clean up the terminals and clamp with some abrasive

#6 Arno


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Posted 30 October 2019 - 01:51 PM

And check that the clamps on the battery terminals haven't stretched so even with the nuts fully tight they still won't bite down on the posts enough to make good contact. They are made from fairly flimsy pressed steel that deforms/stretches.


Also examine the state of the clamp connection/crimp to the positive and negative cables themselves and also on the ground cable to the chassis rail in the front compartiment.


They can get pretty frayed or corroded inside the clamp and build up a lot of resistance which makes everything fall on it's face when the starter motor tries to pull 100 to 150A through the connection.


Also run some emery cloth or a wire brush and some degreaser over the new battery contacts to remove any oxidation and coating(s) before fitting the clamps to get the best and cleanest contact surface.


Once it all works again, also coat the battery contacts and clamps with some vaseline spray to reduce oxidation/corrosion while in use.


Bye, Arno.

#7 chris-vxt



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Posted 30 October 2019 - 05:48 PM

Thanks for all the pointers...
I removed the clamps, cleaned and refitted making sure everything was tight and it all worked fine!

I’m pleased it’s working but would have rather found something positive that was the cause as I’d be more confident it was sorted for good.

Main thing is it’s all working fine now and I’ll put it down to loose connections.

Thanks for the help


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