In a message dated 11/22/04 9:46:38 AM Eastern Standard Time,
peb3@cornell.edu writes:
<< Turns out the hot lead for both the low and high beams is common and
the ground lead is switched by the relays for the respective lights. >>
Some 80's GM cars did this also. I'm not sure why but I'd suspect having the
+ wire run from the light to the underhood relay and fuse ( shorter distance
) offers less chances of having a + wire rub through/ If the ground wire
rubbed through, the lights would just stay on.
There might also be a chance a ground point near the headlight was difficult
to locate. Rather than running 2 wires some distance from the light, the
circuit was reversed. Less wiring, less weight, smaller package and lower cost.
Harold
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