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chevynut
01-15-2019, 09:36 PM
I've been looking at flashers and I see they're available in 2, 3 4, or even 5 pins. Some have a wire coming out of the case. The pinouts are all different, with power, load(s) and grounds on different pins. What a confusing mess.

I see mechanical (bimetal) flashers and I know how they work, and they're usually 2-pin and typically won't work with LED lights. Then I see hybrid (electro-mechanical) flashers that use electronic circuitry to open and close a relay independent of load. Some of these are 2 pin and some have 3 or more pins. Since there's electronic circuitry involved I don't understand how they can get by with 2 pins, just power and a load, and without a ground....or maybe that's why some have the wire coming out of the case? But I also see 3 pin flashers with the external wire. Then there's the all electronic flashers that don't have any contacts, and switching is done by transistors inside. I don't think these make sound when they switch and I want to hear when they're working.

I see "combination" flashers that run both hazard lights and turn signals. However, I can't find any internal wiring diagrams that show how they work. Some have 3, some have 4, and some have 5 pins. Not sure what the difference is internally.

So.....I have a Flaming River column and it uses a "Standard" GM wiring scheme. It has a separate power input for the hazard lights and one for the turn signals. I thought I used to know why you couldn't use one flasher for both, but I can't remember. I think it's because you want flashers to work without the key on, and the turn signals to only work with the key on. Is there any other reason for two flashers?

I want to use LED taillights, rear brake/turn signals, and front park/turn lights. So I need an electronic flasher (or two) of some kind. I think I want a hybrid flasher so I can hear it when the turn signals are on. It would be nice to do it with ONE, but I do want the turn signals to only work with the key on. Can ONE combination flasher do that? If not, what type do I use and how do I identify one from the other?

chevynut
01-15-2019, 11:00 PM
Spent another hour or more looking at more flashers and I think I found exactly what I need. :)

I was trying to avoid taking up two relay sockets by using only one flasher, and I believe the 5-pin EP-27 does just that. It has two separate power inputs, one for ignition power and one for constant power. There is one ground, and two outputs that are independent of each other. It does make a sound from what I have read so it should work as planned and free up one socket. It's commonly available at Autozone and other parts stores too.

https://images-na.ssl-images-amazon.com/images/I/410J4aFLZmL.jpg

I also found out that the Flaming River column disconnects the turn signal power internally when the hazard lights are activated. Thought I had this electrical stuff all figured out but I keep learning something new. :)

Rick_L
01-16-2019, 07:25 AM
I think it's because you want flashers to work without the key on, and the turn signals to only work with the key on.

I think this is the main reason, but you may be way ahead of me after researching this.

My wire harness has 2 pin flasher provisions on the fuse panel for hazard and turn. Why would I want something different? Would I have to run wire connections on these terminals to a socket that looks like a relay socket?

chevynut
01-16-2019, 08:10 AM
My wire harness has 2 pin flasher provisions on the fuse panel for hazard and turn. Why would I want something different? Would I have to run wire connections on these terminals to a socket that looks like a relay socket?

If you're using a pre-built harness like an AAW or Painless one that takes standard 2-pin "can" flashers, it makes no sense to do what I'm doing. My fuse panel is built from scratch using snap-together "blocks" of 4 fuses each. I have several relays and will probably need more, so I'm trying to conserve relay sockets. This EP-27 flasher frees up one socket for me to use for something else like my door lights, since I have to invert the dome signal from the door switch and can't figure out how else to do it. I wish the DD PAK-1300 dome light controller had an output to do that but it doesn't. I have 4 relay sockets in front of the firewall (all used), 7 sockets behind the firewall, and 9 sockets in the console. I think all but two are committed to specific functions at this point.

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