I changed the battery in my 1994 Mazda MX-5 and now it won't start - what could be wrong?

I recently fitted a new battery on my 1994 Mazda MX-5 after making a few small journeys and it started with no problem. I returned home and within half an hour the alarm sounded a few times and then clicking began and the car wouldn't start. I tried jump leads but they smoked and melted.
You must have connected pos to neg and neg to pos and fried the ECU.
Answered by Honest John on

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