Connecting a battery charger backwards to a battery will likely kill the battery, depending on how long the power is attached.
Blown fuses, melted wiring, computer damage,
Damage to the alternatoron both can occur and permanent damage to the batterries also can occur. Always be sure of +positive to +positive and -negative to -negative if unsure do not attempt to jump vehical it can be a costly mistake It can "fry" the alternator, the computers, wiring, fuses, and the battery.
There is the possibility the battery could blowup. You can damage the complete electrical system.
Car battery charges can check the damage done to the actual battery but to the entire car is another story
Yes it will damage your battery if you reverse the cables. There is an article on Wikipedia about it at this link http://en.wikipedia.org/wiki/Rechargeable_battery.
When you connect the battery backwards you can cause major damage. You can blow the alternator or its fusible link. You can destroy electronics, particularly the various computers - and these are not cheap.
No, and you may do major damage to the computers.
no- if you connect a battery the wring way round you will short the battery on a modern car you may damage the ECU
It depends on the battery charger. Some chargers will detect that they're hooked up backwards and do nothing. More than likely though it will dis-charge the battery pretty quickly, and probably damage it.
no as long as you don't put the cables on wrong
when you reverse connect a battery there is a good chance you will blow the main fuse this will protect the car from more damage but usually stops the battery for been charged as well... check and change the main fuse or fuseable link The alternator probably already was bad before you put the battery in.