Land Rover Forum  

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A final note about terminal markings: Later production ignition coils were marked "+" and "-" on the primary terminals, which makes hook up pretty much self-evident. The primary terminals of early coils for positive earth setup were marked "SW" for Switch, and "CB" for Contact Breaker". In the positive earth system the ignition switch supplies power from the Negative battery post, and the contact points ground the other side of the coil to the Positive battery post. Therefore "SW" = "-" and "CB" = "+". This bit of knowledge and logic can avoid confusion if you change your vehicle from positive earth to negative earth. In that case you reverse the coil wires, and the "CB" terminal connects to the positive Switch wire while the "SW" terminal gets grounded to negative through the Contact Breaker. If you're still confused, buy a new coil with the "+" and "-" markings.