MG Car Repair: MG Wiring mess, hot shows, would make sense

Question
Hey Howard. My uncle just picked up an older MG...don't have specifics on it (early '80's) but he is having a mess with the wiring and I'm trying to give him a hand. We are mostly wondering if these cars are wired with any special tricks or odd design when compared to your typical American made car. Doesn't seem to be as simple as just tracing wires from load to source. It's almost as if some systems suggest a "grounded" circuit when not energized as opposed to "open" as would be expected. For instance, according to the schematic...a wire that is used as a "hot" shows "grounded" with the key off. This would make sense if there were an relay, but it should be an open circuit when not energized and not grounded. We are a bit confused as this seems very untraditional. Is there some secret to these wiring systems that we need to know about, or are they just like any other car?

Answer
Hi Bruce,

No, nothing odd about the wiring. In fact it is one of the best as the color coding is very uniform and easy to follow.

You need to give me the year and model of the MG and what circuit you are tracing for me to try to help. Only pick one circuit at a time to trace.

Howard