New battery fitted the wrong way round.

[Stucp]

Hello,
This is my first post on the forum.
I have recently bought a Citroen C15 van 2002 1.9d DW8 last August and was planning on doing it up.
I am ok at body repair work, painting and changing seats etc but I am no mechanic and only experienced really in servicing and changing the odd engine bit here and there.
The C15 needed a new battery as the existing one was no longer able to start the engine having got steadily worse since I bought the van.
In my rush to get it done this afternoon with other things on my mind and it getting dark, I stupidly fitted the battery the wrong way round.
I even tried to start the van with it like this.
There were a lot of sparks and electrical burning fumes.
The engine won't start now. the light for the glow plugs on the dashboard doesn't come on at all now.
The engine turns over but does't fire.
Have I just caused irreparable damage to the engine ?
Have I burnt out a component like the glow plug relay box?
Is there any chance I may only need to replace some fuses?
I am really annoyed with myself for getting such a simple task so wrong.
I have also tried to start the engine with the terminals now fitted correctly but still no glow plug light on dash and engine doesn't fire.
The negative lead clamp, I discovered today, is actually falling apart so I tried getting it to clamp a bit tighter on the battery pole with the help of a nail but still wasn't tight enough but tried jump starting it anyway from my car but still same problem.
Would greatly appreciate some expert advice.
Many thanks indeed,
Stuart.

[xantia_v6]

If you are lucky it will have blown some of the large fuses and done no other damage. Most of the electronic components are designed so that they are isolated by a diode or relay and don't get fried by a reversed battery.

The most vulnerable part is the alternator, which may well be cooked, along with some of its wiring.

You need to locate the fuses and check them all. If that does not fix it, then you will need a wiring diagram and multimeter to work out what is broken.

[white exec]

I think you should get the car to an auto-electrician, or someone who knows their way around vehicle electrics.
Fortunately, the C15 has a limited number of electronically sensitive components, and hopefully most will have survived.

The battery connectors and terminals are different sizes for a good reason! Hopefully not a mistake you will make again.

[wheeler]

With a bit of luck you have just blow a fuse for the glow plug system. A DW8 engine is almost impossible to start from cold if all 4 glow plugs are not working.
Check all the fuses, I recently looked at a Micra that wouldn’t start after someone connected jump leads round the wrong way & it had blown 3 different fuses.

[white exec]

The GPs are not normally fused, iirc.

[wheeler]

The GPs are not normally fused, iirc.

Correct, the glow plugs themselves are not fused however the control signal to the primary side of the glow plug relay is. If this fuse has popped the glow plug circuit wont even power up.

[white exec]

That's right. The control side could well be down.