Originally Posted by Danieljta
The car came with no stereo or cigarette lighter, and a malfunctioning power antenna (ran constantly with antenna stuck up) I just pulled the antenna out for a rebuild(broke plastic cable)
Thanks everyone for the help!
There ya go.
The yellow is the trigger for the power antenna. Connects to the "antenna" lead at the factory or even aftermarket radio. You verified this by noting the orange and black wires with the yellow at the relay plug.
Some clown hooked it to constant hot(lighter) and ended up clipping it to try to stop the constant running antenna.
Why someone hooked the yellow to the lighter is the mystery!