High Beam Operation

High beam operation is enabled by pulling the Multi-Function Lever (turn signal) towards the driver. If the low beams are already on, the headlamp system will change state to high beams. If the low beams are not on and the Ignition Switch is in RUN, the high beams will turn on for as long as the Multi-Function Lever is pulled and held inward (Flash-To-Pass).

When the Multi-Function Lever is pulled inward, the Headlamp Dimmer Switch closes, sending an input to terminal B8 of IPC connector C2. In response to this input, the IPC sends a request via the Class 2 serial data line to the PZM to activate the high beam headlamps. The PZM provides a ground for the coil of the High/Low Beam Headlamp Relay "C." The coil is then energized causing the switch contacts to close and apply voltage through the L HDLP HI Fuse and R HDLP HI Fuse to the LH and RH High Beam Headlamps, respectively. For Eldorado/Seville, the RH High Beam Headlamp is grounded to G101 and the LH High Beam Headlamp receives ground through Daytime Running Lamps Relay "F" from G101. For DeVille, the LH and RH High Beam Headlamps are both grounded to G101. When the switch contacts of High/Low Beam Headlamp Relay "C" close, voltage is removed from the Low Beam Headlamps causing them to turn off when the high beam headlamps are on.