Acura 39794-SDA-A03 Power Relay Assembly

Many electrical accessories, such as the fuel injection system, horns, starter, and fog lamps, utilize relays to manage current to components, employing a low-current control circuit to operate a high-current power circuit. A defective relay will prevent the associated component from functioning, and these relays can be found in the engine compartment fuse/relay box and near the under-dash fuse and relay box, with access to the under-dash relays requiring the removal of the left kick panel. There are two primary types of relays: normally-open type A and five-terminal type A. Normally-open type A relays serve various functions, including ABS fail-safe, accessory power socket, air conditioning components, and multiple light relays, characterized by four external spade terminals arranged in a specific configuration. Testing involves checking for continuity between designated terminals with power applied or disconnected. Normally-open type B relays, used for systems like the ABS pump motor and blower motor, also feature four terminals but arranged differently. Five-terminal type A relays, utilized for windshield wiper control, have five terminals in two rows, and testing requires verifying continuity between specific terminals under certain conditions. Five-terminal type B relays, which serve functions such as ACC cut and moonroof controls, follow a similar testing procedure to ensure proper operation.

Some electrical accessories controlled by relays in vehicles include the fuel injection system, horns, starter, and fog lamps.