Lighting and Horns: Description and Operation

Fig. 3 Brake Lamp Switch:

BRAKE LAMP SWITCH
The brake lamp switch is located under the instrument panel at the brake pedal arm. The brake lamp switch has three internal switches that control various electrical functions of the vehicle.

The brake lamp switch has three internal switches that control various electrical functions of the vehicle. The main function of the brake lamp switch is to control the operation of the vehicle's brake lamps.

When the brake pedal is pressed, the plunger on the outside of the brake lamp switch extends outward. This action opens and closes the electrical contacts inside the switch depending on the internal switch in question.

For the brake lamp circuit, this action closes the electrical contacts within the switch, completing the circuit to the brake lamps at the rear of the vehicle. The brake lamps and center-high-mounted stop lamp (CHMSL) then illuminate.

Fig. 7 Combination Flasher Location:

COMBINATION FLASHER
The combination flasher is a smart relay that functions as both the turn signal system and hazard warning system flasher. The combination flasher is designed to handle the current flow requirements of the factory-installed lighting.
The combination flasher cannot be repaired and, if faulty, it must be replaced.

While the combination flasher shares the terminal orientation (footprint) of a International Standards Organization (ISO)-type relay, the internal circuitry is much different. The combination flasher contains active electronic integrated circuitry elements. Do not substitute any other relay for the combination flasher.

Because of the active electronic elements within the combination flasher, it cannot be tested with conventional automotive electrical test equipment. If the combination flasher is believed to be faulty, test the turn signal and hazard warning system circuits. Then replace the combination flasher with a known good unit to confirm system operation.

If supplemental lighting is added to the turn signal lamp circuits, such as when towing a trailer with lights, the combination flasher will automatically compensate. This allows the flash rate to remain the same, regardless of electrical load increases. However, if a bulb fails in the turn signal lamp circuits, the flash rate of the remaining bulbs in that circuit will increase to 120 flashes-per-minute, or higher.

Multi-Function Switch:

MULTI-FUNCTION SWITCH
The multi-function switch assembly is mounted to the left side of the steering column. This switch contains circuitry for the following functions:
- Turn signals
- Hazard warning
- Headlamp beam selection
- Headlamp optical horn
- Windshield wipers
- Windshield washers.

When the driver wishes to signal his intentions to change direction of travel, he moves the lever upward to cause the right signals to flash and downward to cause the left signals to flash. After completion of a turn the system is deactivated automatically. As the steering wheel returns to the straight ahead position, a canceling cam molded to the clock spring mechanism comes in contact with the cancel actuator on the turn signal multi-function switch assembly. The cam lobe, pushing on the cancel actuator, returns the switch to the OFF position.

If only momentary signaling such as indication of a lane change is desired, the switch is actuated to a left or right intermediate detent position. In this position the signal lamps flash as described above, but the switch returns to the OFF position as soon as the lever is released.

When the system is activated, one of two indicator lamps mounted in the instrument cluster flashes in unison with the turn signal lamps, indicating to the driver that the system is operating.