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In-general, yes, especially in recent years. Keep in-mind that relays are used in 101 different ways to accomplish some pretty interesting tasks that can seem a bit puzzling at first glance. So, it is not uncommon to find them wired in quite weird ways (OK - really weird) even from the factory. Also, the factories are using more and more specialized or proprietary relays that have different in/out schemes or added internal circuits. The info above is strictly for the most common aftermarket relays known as the 'Bosch' type. Others will not have the same numbering system or configurations.

More useless relay trivia: The Ford starter 'solenoid' is yet another name gifted to us from the Chevy guys. It's a relay, but the average guy regarded it like the solenoid on GM starters - which it is not. None-the-less, the name (just like th GM "Posi" term) has been used so long it has stuck permanently. This is why you will find it listed as both a relay and a solenoid in parts stores and manuals.

Due to the voltage spikes that standard relays produce when turned on and off (like a mini ignition coil), they can be used purposely that way. One of the Forum members had an MSD ignition triggering a tach and it just didn't work. None of MSD's suggestions worked either. So I made him a tiny tach adapter from a relay coil to simulate an ignition coil feedback to the tach. Creating 200 to 400v from the 12v MSD signal wire was enough to make the tach work.

Relays have been used in some creative ways, such as flame-thrower spark generators and afterburner ignitors. To make exhaust tip flames, fuel is injected into the exhaust (or fed extremely rich on engine decel) and it lights-off with exhaust heat. Usually. But to ensure it, especially in show and parade cars where the exhaust doesn't get very hot, spark plugs are often added to the exhaust (or jet car tailpipe) and an ignition coil is triggered for a constant buzz of sparks by two daisy-chained relays. The 1st relay turns on as normal, energizing the 2nd relay, which turns the first one off, creating a constant on/off signal to the coil. Bingo - instant afterburner ignitor, elephant stun gun, etc.
:D
David

EDIT: BTW - that last example is similar to how power window and door lock relays are wired for up/down depending on the switch direction or button pushed. They just aren't chained to self-cycle like the example. :tup:
 

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LOL... thanks for relaying your thoughts.
 

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Re-post of the image that apparently was lost in the forum reconstruction. The 5-pin relay is shown OFF with power flowing from pin 30 to pin 87a. When energized with power on pin 86, the contact moves from pin 87a to pin 87, sending power to the load on that pin. Some relays are 4-pin, and do not include pin 87a:
 

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