What is the purpose of a relay in a 12 volt system?
In 12-volt automotive circuits, even small resistance amounts can cause significant voltage drop. Relays provide a solution by shortening the required length of the heavy-gauge, power-delivery wire from the battery or alternator to the load.
What is 86 on a relay?
Realizing that 85 and 86 are the coil pins, these pins will be transferring the current through the coil. 85 will be used to ground your relay, while 86 will be connected to the switchable power. 87 and 87a will be connected to your controlled accessories that you wish to turn on and off with your relay.
What is 87a used for on a relay?
87a completes the circuit with 30 when the coil is not energized. This is how most alarm starter kill relays work.
How does a 12 volt DC relay work?
Most 12 volt relays operate the accessories in cars and other motor vehicles. When you apply a small amount of current to the relay coil, this closes contacts which in turn feed power to an accessory which would normally require a lot of current to operate. Connect the wires to your relay’s coil.
What’s the color of the EEC power relay?
The EEC Power Relay is easy to recognize because it’s usually a brown color. If the EEC Power Relay has already been replaced, you can still recognize it by its brown colored connector. In this ‘How To Test’ article, I’ll show you how to test it on your Ford car or pickup in a step-by-step manner.
Where does the power come from on a Ford EEC relay?
This voltage comes from the ignition switch. Power (in the form of 10 to 12 Volts) is always present in circuit 4 . This voltage comes directly from the battery positive terminal across a fusible link on the starter motor solenoid (on the fender). Ground is always present on circuit 1.
Where does the power come from in the Brown relay?
Power (in the form of 10 to 12 Volts) is applied to circuit 2 . This voltage comes from the ignition switch. Power (in the form of 10 to 12 Volts) is always present in circuit 4 . This voltage comes directly from the battery positive terminal across a fusible link on the starter motor solenoid (on the fender).
