AW2: Check Illumination Lamp Ground

With the ignition key in the OFF position, disconnect the inoperative single illumination source. Turn the headlamp switch to the parking lamp position or the headlamp position. Operate the headlamp switch from the dimmest position to the brightest position. Measure the voltage on the Pink/Black wire at the inoperative single illumination source connector while operating the light switch rheostat resistor. See WIRING DIAGRAMS  . Does the voltage vary from approximately 9 volts (dimmest position) to approximately 0.2 volt (brightest position)? If yes, replace the miniature bulb or switch. See SWITCH LAMPS (MINIATURE BULBS)  under REMOVAL & INSTALLATION. If no, service the Pink/Black wire.