Many of the circuits in today's car and trucks are protected by a circuit breaker. The circuit breaker comes in three different types--plug-in, inline and tab-mounted. While the failure of a circuit breaker is rare, replacement is sometimes necessary, and is a task easily handled by the car owner.
Check your owner's manual for the location of the circuit breaker which protects the problem circuit. Modern vehicles have as many as three electrical distribution panels making finding a failed circuit breaker very difficult without the manual.
Determine the type of breaker. A plug-in breaker will be inside a power distribution panel, while a tab-mounted breaker will be attached to the vehicle with a rivet or screw, and an inline breaker will be installed along the wire.
Grasp a plug-in breaker firmly and gently pull it directly away from the panel to remove it. Install the replacement breaker by pushing it straight into its holder. Don't be concerned about polarity, as a circuit breaker can be installed in either direction.
Remove the two small nuts from a tab-mounted or inline breaker to detach the wiring from the studs. It is a good idea to disconnect the negative cable from the vehicle battery first.
Remove the screw holding the circuit breaker to the vehicle. Some tab-mounted breakers are held in a plastic bracket. To remove, pull the breaker out of the retainer until the tab is released. Reverse this step to install the new breaker.
Know that an in-line breaker is held only by the wiring to which it is attached. Removing the wiring from the studs releases the breaker, so you simply have to install the wires to a new breaker to replace this type of breaker.
