I haven't used my car for a couple of weeks and as it's been so cold it wouldn't start due to a flat battery. My neighbour was kind enough to help me try and jump start it. I put the leads on my battery he put the leads on his. After trying for about 15mins the donkey realised he put the leads round the wrong way on his terminals When he left my dad turned up so we tried with his car and it still wont start. Could putting the jump leads on the wrong terminals have caused much damage? I'm guessing at best it's fried the battery or blown a fuse and worst ecu? starter solenoid?
Any thoughts?
It's booked for it's mot today.