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The catalytic converter in your auto exhaust system is a pollution control device designed to stop smog by turning unburned hydrocarbons and combustion byproducts of engines into normal atmospheric gases, said the PollutionIssues.com website. This device, which became mandatory in the 1980s, turns the carbon monoxide, nitric oxide and hydrocarbons of engine exhaust into carbon dioxide, nitrogen gas and water vapor. Catalytic converters have 3 main components: Catalysts, substrate and outer can.

Catalytic Elements

In chemistry, a catalyst is a substance that triggers chemical reactions without itself being consumed by those reactions. Catalytic converters use platinum, rhodium and cerium as the catalysts that clean up exhaust gases. As exhaust gases pass through the converter, these materials get extremely hot, about 750 degrees Fahrenheit, and trigger oxidation reactions that break down passing exhaust gases into normal atmospheric gases.

Ceramic Substrate

Inside the converter is a honeycomb-like ceramic substrate that has been coated inside and out with the catalytic elements. This structure provides a huge surface area for the oxidation reactions to occur, said PollutionIssues.com. Tetraethyl lead, once widely used as a gasoline octane booster, was removed from gasoline in the early 1980s because it would coat the substrate, blocking the catalytic reactions. In effect, lead poisoned the converter.

Outer Can

The outer metal can holds the interior components in place. It typically is a steel cylinder with fittings to connect to the exhaust manifold at one end and the exhaust pipe at the other. The can is lined with an insulating mat to help hold in the heat that ensures efficient operation.

Windshield washing components all have specific jobs to do and they work in concert with each other to accomplish the major task of keeping the front or rear windshield surface clean and clear of debris. The entire system relies on pumps, motors, wiper arms and blades, reservoirs and windshield washing fluid to get the job done. Any one part can fail and result in the breakdown of the system.

Wiper Blades

The wiper blades, made of rubber and sometimes having two or three blades, wipe over the window creating a seal that removes excess water and debris. They form a squeegee-like seal that always keeps force on the glass surface by use of a spring in the wiper arm. With a control knob on the dashboard or steering column, the speed and frequency of the wiper blade can be controlled.

Wiper Arms

The wiper arms hold the rubber wiping blades in place with slots or snap-connectors. They have special metal hinges that allow for flex on curved surfaces. The base of the wiper arm has a spline slot for connection to the wiper motor main shaft. The wiper arms can be replaced as a unit which contains the arms and the rubber wiper blade inserts in one component.

Windshield Wiper Motor

The windshield wiper motor sits inside the front windshield galley area. The motor contains an armature and a coil. The motor runs off the batterys 12-volt system and powers the windshield washing linkage arms by turning a splined shaft in a constant 360-degree rotation. The motor has a relay and fuse that protect it from overload and shorts.

Windshield Wiper Linkage

The windshield wiper linkage consist of a number of rods that have hinged ends and connectors. The linkage arms, driven by the motor, permit a reciprocal motion that turns into a back-and-forth wiping motion. They travel back and forth with approximately a 130-degree arc, repeating the wiping motion so long as the motor drives it. The linkage arms require periods of lubrication to keep them from binding and to keep them turning smoothly.

Windshield Washer Reservoir

The windshield washer reservoir consists of a plastic tank, usually bolted against the firewall inside the engine compartment. It holds washer fluid to a certain level, dispersing it through the use of a pump and feed line. The contents of the washer tank usually hold a mild soap-and-water solution or a factory-approved cleaning fluid.

Windshield Washer Fluid Pump

The windshield washer fluid pump sits below the tank, recessed into the plastic mold. It runs on the batterys 12-volt system. It is designed to force washing fluid through a small plastic or rubber hose that travels up to the base of the wiper arm where the fluid gets sprayed on the window. The windshield washer electrical system protects it with a fuse and a relay.

Rear Windshield Washing System

Many vehicles, including Toyotas, have a complete duplicate windshield washing system located in the rear of the vehicle to clean the rear window glass. They have only one arm and blade to clean a large rear view area. This arm and blade must be longer to accommodate a single surface area. The reservoir and pump typically sits in a recessed quarter panel area that has access through a flip-top lid. Linkage, driven by a motor, operates in the same fashion as the front window system.

Motor and Washer Delay Control

The motor and delay control device actuates by an electronic circuit that senses a pulse that makes it operate only for a specific period of time. A separate electronic circuit allows the pump to pulse, releasing fluid for the wash cycle.