Help - installed a new battery the wrong way round!

Maybe new battery bad and doesn't have the power to start. Borrow a battery and try again, or get a jump from someone..
 
This thread has made me wonder why a fuse would blow, from reversing the polarity on the battery.

That alone wouldn't cause a short circuit and blow a fuse; the chassis would simply be positive instead of negative (and a lot of things wouldn't work as intended, or become damaged).

And then it dawned on me, could the blown fuses be part of a reverse polarity protection circuit, for the devices that may suffer damage?

So in effect, the fuses were deliberately blown by a direct short caused by built-in protection, rather than by simply just reversing the battery.

I wonder if anyone here can confirm that?
 
So in effect, the fuses were deliberately blown by a direct short caused by built-in protection, rather than by simply just reversing the battery.

I wonder if anyone here can confirm that?

Electronics, often have diodes installed, simply to protect the circuitry from reverse polarities, so the fuse will blow rather than doing more serious damage. I beleive they are called 'sacrificial diodes'.
 
Maybe new battery bad and doesn't have the power to start. Borrow a battery and try again, or get a jump from someone..
I've tried to jump start it with both the new and old battery. No cranking happens, just the click when I turn the ignition on.
 
Was the old battery capable of starting the car before the battery change? Having 2 bad batteries doesn't make a good one.
 
I think modern alternators need fuse protection......for sure they weren’t years ago and would always fail if incorrectly connected.
In this instance, checking the fuses ( and any sacrificial links) is about all we can do.
Do check for blown fuses / links at the positive cable where it connects to the battery.
John
 
I remember years ago on some Ford cars (Mk3 Escort, Capri, Granada etc.) when changing the battery, people got a similar result as the OP. This was because when undoing the leads, a single wire on the positive terminal had fallen down unnoticed by the side of the battery. I don’t suppose the OP's car has a similar setup, does it?
 
I remember years ago on some Ford cars (Mk3 Escort, Capri, Granada etc.) when changing the battery, people got a similar result as the OP. This was because when undoing the leads, a single wire on the positive terminal had fallen down unnoticed by the side of the battery. I don’t suppose the OP's car has a similar setup, does it?
Or even an earth lead
 
Not sure i see the issue with ensuring the battery has enough cranking amps in it in the 1st place.
Omit the obvious.

Every new battery i've ever bought got stuck on the charger for a few hours before fitting.

Diesels are particularly amp hungry.
 
Think there are 2 locatiosn for fuse box, this vid shows main location under bonnet and one is in the , the vid is for left hand drive but location is similar. You should be able to pull the smaller ones out to see if any ar ebroken:


I blew a fuse in sept on mazda6 when changing a part, teh fuse was located under the dash of footwell front passenger location.

good luck
I've only just seen your post.

That's a very informative video, thanks for posting it
 
Was the old battery capable of starting the car before the battery change? Having 2 bad batteries doesn't make a good one.
No, it wasn't, but the car started with jump leads.

Since the 'incident', the car won't start with either battery, even with jump leads.
 
I remember years ago on some Ford cars (Mk3 Escort, Capri, Granada etc.) when changing the battery, people got a similar result as the OP. This was because when undoing the leads, a single wire on the positive terminal had fallen down unnoticed by the side of the battery. I don’t suppose the OP's car has a similar setup, does it?
I don't think so. It looks like this:
 

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