Turn Signal Switch: Description and Operation

Fig.18 Multi-Function Switch:

MULTI-FUNCTION SWITCH
The multi-function switch is secured to the upper steering column housing at the top of the steering column, just below the steering wheel. The visible parts of the multi-function switch are the turn signal control stalk that extends through a dedicated opening in the left side of the upper steering column shrouds, the windshield wiper/washer, exterior lighting control stalk that extends through a dedicated opening in the right upper steering column shrouds, the hazard warning switch push button that protrudes through an opening in the upper steering column shroud on the top of the steering column. The remainder of the switch, its mounting provisions, and its electrical connections are all concealed beneath the steering column shrouds. The multi-function switch control stalk has both nomenclature and International Control and Display Symbol graphics applied to it, which identify its many functions. An International Control and Display Symbol icon for "Hazard Warning" is applied to the top of the hazard warning switch push button.

The switch housing and its controls are constructed of molded black plastic. A connector receptacle with up to twenty terminals is located on the back of the switch housing and connects the switch to the vehicle electrical system through a take out and connector of the instrument panel wire harness.

The multi-function switch supports the following functions and features:
- Continuous Wipe Modes - The control knob of the multi-function switch provides two continuous wipe switch positions, low speed or high speed.
- Intermittent Wipe Mode - The control knob of the multi-function switch provides an intermittent wipe mode with multiple delay interval positions.
- Washer Mode - A button on the end of the control stalk of the multi-function switch provides washer system operation when the button is depressed towards the steering column.
- Hazard Warning Control - The internal circuitry and hardware of the multi-function switch provide detent switching for activation and deactivation of the hazard warning system.
- Exterior Lighting Control - The internal circuitry and hardware of the multi-function switch provide for activation and deactivation of exterior lighting.
- Headlamp Beam Selection - The internal circuitry and hardware of the multi-function switch provide detent switching for selection of the headlamp high or low beams.
- Headlamp Optical Horn - The internal circuitry and hardware of the multi-function switch includes momentary switching of the headlamp high beam circuits to provide an optical horn feature (sometimes referred to as flash-to-pass), which allows the vehicle operator to momentarily flash the headlamp high beams as an optical signalling device.
- Turn Signal Control - The internal circuitry and hardware of the multi-function switch provide both momentary non-detent switching and detent switching with automatic cancellation for both the left and right turn signals.

The multi-function switch cannot be adjusted or repaired. If any function of the switch is faulty, or if the switch is damaged, the entire switch unit must be replaced.