Right so it turns out that the altornater i had in was a 55a and i replaced it will a 70a could that be the problem ??? ive ordered a new 55a one with the 3 prong plug is that all i need to plug in ?? because the new one i have ordered had a little terminal with a w on it but there are no other cables apart from the 2 reds and the blue that is connected to the 3 prong plug ?