lights on 1995 Oldsmobile Achieva

i have head lights but no tail or dash lights. i changed the fuse just to be sure but still no lights

Asked by for the 1995 Oldsmobile Achieva
Is the brown wire live at the back of the car when the light switch is turned on? It brings power to the tail lights and license plate light if no power here you have to test at the light switch itself.
Does the 20 Amp fuse marked "tail lamp" in the fuse box have power using a test light or preferably voltmater? If so the orange wire at the light switch should have power. After these two tests a wiring diagram is needed to do continuity tests on the light switch to see if it has failed.
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