I am looking for a relay that has:

1 LOAD Connector
1 PWR/BAT Connector and
2 SWITCH connectors

I need a relay that will activate with two different switching options.

Does that make sense? Does it exist?

I would also greatly prefer a plug in type relay...


OR, could I just attach both switch wires to the switch terminal? If I did that, would it back-feed powere to the other switch component wire?

 

There is no relay like that that I know of. You could hook up both switches to the relay coil and diode isolate both to keep them from back-feeding.

 

This is why I leave electricity and such alone... LOL!

RP

 

I think you can achieve what you want by using two relays that are activated by one switch. Find a switch that is off in the center position and on in the up or down position. The relays would be better off seperated because if one goes bad the other still works.

 

What exactly are you trying to do?
On my Bronco I had an alarm that would allow the rear window to roll up or down with the remote. I had to hook up 2 relays to get it done.

A regular Ford relay has 2 contacts that are always closed with no power and 2 contacts that are closed when swiched.

 

I am trying to hook up aux. back up lights that will come on with the reverse lights automatically but with the option of using an in-cab switch.

Any suggestions...?


Robdude30, Tell me more about the diode stuff......

 

I put aftermarket foglights on my Eclipse, but used an OEM switch. Since it didn't have a circuit wired for the lights I used two relays. The first was triggered by the OEM switch feeding from the battery. The second was triggered by the hot lead to the parking lights and feeding from the output of the first relay. This allowed the fogs to come on when the parking lights were on, but still gave me the option to turn them off with an OEM switch, so other than the lights looking a little different it was just as if it came from the factory that way...

hope that helps...

 

Phil.

Yes you could do the dual SPST relays and the Diode, or do a DPDT relay config to interrupt the power to one of the coils ( I put this drawing in my Misc Album in my Gallery if you want to look at it, it is ugly ).

Rather then go to all this pain, why not just use a SPDT switch in the cab, instead of a SPST switch ?

If you have a EVTM, find the reverse circuit in the cab in the harness you can even put the relay under the hood, or in the cab of the truck, rather then under the rear bumper, and run only the output of the relay to the rear of the truck, rather then running the power and the switch lead from the front to the rear, and putting the relay back there.

Right now I cannot get another picture into the gallery, I can email it to you if you’d like, just drop me an email and I’ll send it off to you. So here goes with the describing of the setup.

The SPDT switch can take a single input to either of the 2 outputs, or if you wire it as 2 inputs to a single output I guess it might be called a DPST switch ( no there really is no such product, that is just how the poles and throws are being used ). Sorry if that is too basic, I’m just trying to make sure I cover all the descriptions correctly.

The inputs ( the DT side of the switch ) 1 is the “constant” power source you want to use ( say ign, parking lamps, etc ) the other is the reverse lights ( use a EVTM to find the backup circuit in the cab, or a fused connection all the way from the back to the front again ). The single connection ( SP ) is now a output to the coil of the relay.
So with the switch one way, it is taking power from the reverse lights to power the relay coil, the other position it is taking power from the “constant” source you selected to power the relay coil.

Real simple, no diodes, no additional relay, and you can mount the relay anywhere up in the front of the truck if you want to.

Let me know if you need the picture emailed to you, or I’ll repost once I can get to the gallery database again.

Let me know if you have any other questions

Steve

 

I like Steve's idea since you mentioned that you will be tying into an existing circuit (the backup lights) on one side.

Simply put, diodes only pass voltage/current in one direction (over simplified). Properly used, they will keep your accessories from backfeeding into the trucks wiring and causing undesired operation. If you would like to learn more about diodes, check out www.the12volt.com . They have a good technical section that explains them pretty well.

 

Here is the diagram for the config I was trying to describe:



Let me know if you have any questions on it,

Good luck

Steve

 

Steve,

PW1981 has the trailer tow option. Could you not just splice into the tow harness at the rear and run a wire to the lights from there. Add a switch w/fuse to power the relay and presto.

JMC

 

JMC,

That is exactly what I did. I took the diagram above, switch included and mounted it at the rear of the truck. The switch is under the cap, and allows for me to select between constant run or backup mode of the Truck Lite LEDs that I have mounted back there.

Phil said he wanted the switch for the constant run in the cab of the truck. Either way ( unless I am missing something ) there is a wire from the front to the rear to get the switch in the cab, for the constant run postion.

Let me know if I missed a way of having the constant run switch in the cab usign your method.

 

Steve,

Run a fused + wire to a SPST switch then to the power side of the Trailor Tow reversing lamp relay coil. It will get power from the switch being on and energize the coil, send power to the Trailor Tow back up lights only. Or if the truck is put into Reverse the DTRS switch will energize the coil and turn on the lights. If both the switch is on and you put it in reverse , no biggie, just 2 Positive leads going into the Relay. Look on Page 95-3 of the EVTM. Run the Switched + to circuit #140 on the relay.

JMC

 

Steve... that looks great and very easy to understand. I may take it one step further and put in a 3-way switch with an 'off' setting in addition to the 'on' and 'backup' settings.

Thanks to everyone for the help, I think I am set to go now. I just need to find a small switch that I can install un-obtrusively in the cab. Anyone know a good place online to look at pictures of switches so I can find an attractive one

 

Ok, I have been looking thru the EVTM trying to find a place to t-tap in the cab for the reverse lights and am having no luck. I know that the BK/LG wire to the 7-pin harness is the one for the trailer backup lights (after I install the relays in the under hood box). That seems like a natural choice of wires to use, but do you know if this comes thru cab at any point? Maybe in the wire looms under the floor panels on either side?

Any help locating a backup wire in the cab is appreciated at this point. I don't fully understand all the EVTM diagrams yet. A few more projects and I will be there

I found a switch at Radio Shak's web site that I like the look of, but they don't label if its a SPDT switch or not, I'd like to have the illumination when they are in constant on as a reminder, but I am not sure of the switch config: http://www.radioshack.com/product.as...5Fid=275%2D731

Anyone know?