Acura 39792-SDA-A01 Relay Assembly (Micro Iso)

These cars have a number of electrical add-ons, such as fuel injection system, horns, starter and fog lamps, which are controlled by relays that ensure transmission of electric signals to the respective components. By allowing low-current control circuit to open and close high-current power circuit relays function. These relays can be found in the engine compartment fuse/relay box and near the fuse and relay boxes under the dashboard. There are usually three main types: normally-open type-A , normally-open type-B, and five-terminal type ones. The internal circuitry is similar on Type A and Type B relays while they differ in external spade terminal arrangement and numbering. Compared to Type A or Type B relays, five-terminal relays have different internal circuitry plus an added external spade terminal. To test a relay it must be removed from the vehicle and an ohmmeter used to check for continuity. Normally open Type A relays for instance which are used for various purposes such as air conditioning; horns; window lifters have four external spade terminals arranged in two rows. When you unplug them from power sources you should make sure there is no connection between terminals No1 &No2 on one hand but also that there is between terminal No 3 connected to power source via (terminal No 4) a ground wire respectively.The normally-open Type B ones similarly have four external parallel rows of spade terminals just like their counterparts above mentioned for example blower motors; rear defoggers . For these B-type testing is simple which requires breaking connection between contact points No1&No3 when current ceases to flow through them whereas creating path between contacts No1&No3 using their corresponding feeds wires from connectors No2&No4 which are connected with interfaced power line as well as grounded with earth respectively.A last category we will take care about here is five-terminal devices known for moonroof control ; high beam cut-off and others need us to examine continuity between point No 1 &No 4 without power supply whereas later on it should be established by joining terminal No. 3 to power and the ground respectively provided that connection has been completed at points No2&No5. These relay switches are normally discarded as they cannot be repaired.

Relays employ a low-current control circuit to operate a high-current power circuit.