why do my 1998 firebird headlights close when I turn the light switch on and vice versa?
this happened after I replaced the passenger motor gear , and rotated the driver side motor 180 degrees due to grating noise,
Maybe installed wiring backwards or something?
Usually caused by backwards wiring on the motors. Not sure what you meant by "rotating the motor 180 degrees" but if it is not fixed by changing the polarity of the motor leads, I would rotate it back and see if your problem goes away.
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