AR2: Check Instrument Cluster Illumination Control Circuit

With the ignition key in the OFF position, disconnect the instrument cluster connector C1 and the instrument cluster connector C2. Turn the headlamp switch to the parking lamp position or the headlamp position. Operate the light switch rheostat resistor from the dimmest position to the brightest position. Measure the voltage on the Pink/Black wires at the instrument cluster connector C1 and instrument cluster connector C2 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 instrument cluster. If no, service the Pink/Black wires between the instrument cluster and the timer module.