The bumps are usually accompanied by redness and swelling. Allergic eczema is an allergic skin reaction that produces an itchy, red skin rash. The rash may consist of raised, red bumps that ooze, drain, or crust. Angiomas are common skin growths that can form on most areas of the body.
Blower resistors are resistors which are used to control the fan speed of automotive blowers. The fan speed can be changed either by switching the blower resistor resistance mechanically, using a rotating lever, or electronically by the air conditioning system.
The fans are controlled either with a thermostatic switch or by the engine computer, and they turn on when the temperature of the coolant goes above a set point. They turn back off when the temperature drops below that point. Rear-wheel drive cars with longitudinal engines usually have engine-driven cooling fans. These fans have a thermostatically controlled viscous clutch. This clutch is positioned at the hub of the fan, in the airflow coming through the radiator.