Battery - switch for isolation.

Bazzards

Bazzards

Bazzards

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Hi guys

My car has an electrical fault, which means it drains the battery if left connected.

At the moment I have to disconnect the battery whenever I leave the car which is a pain in the rear. Is there anyway of fitting an isolation switch in the cabin? And if so, how easy would it be to fit for a novice?

The car is a 2003 Audi A3.
 

But also, cue 50m posts about how you should be finding the fault not fitting an isolator.
 
If you don't mind popping the bonnet those screw down ones are really quick and easy. I had one on an old Impreza which could be sat for months at a time.

My dad has one fitted on his old series landrover which is within the cabin which is a lot more convenient but a bit harder to fit, depends what amount of effort you want to put in really but i'd say its a good idea as chasing faults in an old car like that is probably not worth the effort.
 
Thanks Soviet, I think I may just live with it. I dont need to do it that often to be honest. I can leave it for an hour or so without issue. A different story if I leave it overnight however.

At the moment I just disconnect the negative terminal.
 
Bazzards said:
Perfect thanks guys. The issue is with the instrument binnacle, £700 to replace, car is not worth that much. :p
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It's unlikely to be the Instrument cluster - that is likely just staying awake as a result of something else (whether that be a door sensor, bad ground, alternator D+ connection)
 
Well it was withan Audi technician for a day. The digital display within the cluster was broken, missing digits etc. Then just stopped working.
 
Definitely worth fitting one of those ones as shown in the YouTube video. The Discarnect ones are worth the couple of quid more over the unbranded ones. Just remember not to fit the fused connection as that is only relevant if you are just using it as an anti theft device.

Your other option is to track down the fuse that disconnects the problem circuit then add an inline switch to disconnect it which could be placed somewhere convenient in the car. There are off the shelf products (designed for towing) but they are about £50. https://www.ebay.com/itm/164024297938

Making your own would be less than a tenner but that relies on you having the kit and confidence to do it yourself.
 
Bazzards said:
Well it was withan Audi technician for a day. The digital display within the cluster was broken, missing digits etc. Then just stopped working.
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Those "technicians" are just fitters like at kwikfit and halfords. All they can do is keep changing parts and hope the problem goes away.
 
I tried one of those switches on the battery, however it did not disconnect completley and I came back to a dead battery. It was not a Discarnect one though. Are they better?
 
Bazzards said:
I tried one of those switches on the battery, however it did not disconnect completley and I came back to a dead battery. It was not a Discarnect one though. Are they better?
Click to expand...
They all do the same job, just some of the non branded ones are a bit flakey quality wise and you don't want that on your main connection to the battery.

The one you tried, did it have a fused connector which is the black lead in this photo?


If so you don't want to be connecting that as it will keep the battery live and only disconnect the power if someone tries to start the car. Basically a simple anti-theft device.
 
It had no wires at all. Just a simple dial on top to disconnect/reconnect. It looked like the image above but without the wires.

That cost me a new battery as it would not hold a charge.
 
Why not disconnect the binnacle and see if it drains, at least try and isolate the issue. You can then go circuit to circuit via the fuses if you prove that it wasnt....
 
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