turn signal, brake priority relay setup

If you view the link below, it will take you to the original topic in which I am unable to post a question since it has been closed.

https://www.the12volt.com/installbay/forum_posts.asp?tid=83462&PN=1&tpn=1

I had the liberty to try the two relay setup using two Bosch 0 332 209 150 12V  20/30A relays, and two 1N4001 diodes.  Since this was an experiment, only one side was put together to test the results.  The experiment involves a bread board, 9V DC battery and associated alligator clips and small gauage wiring. 

I checked and double checked the wiring and I can not get this two relay setup to work correctly.  When the brake and turn signals operate indepently of each other, the circuit works like it should.  Only when both brake and turn signals energized the circuit seems askew.   The test lamp is full bright when the brake is engaged, I then switch the turn signal input off and on and lamp does not fully turn off.  The lamp dims instead of going off.  All the parts are in good working order, I even tried spare relays and diodes to see if they were malfunctioning but they all react the same. 

This project is for my '03 Dodge Caravan that has the red and red brake/turn signals.  I absolutely love the van, but find the rear lights a little shy of safety in the brake/turn signal combo in my opinion. 

I'm scratching my head on this....any help on this topic would be greatly appreciated. 

____

Brian

Let me see if I understand what you need.

2 filiments with 3 functions.

1) Low is regular tail lights with the lights on it is lit.

2) Brakes when break pedal pushed

3) blinker over rides break and only one side blinks while the other still steady.

Hmm Sounds like trailer wiring..

Try this.

One Relay Circuit for each side.

My initial thought was this setup may work, then after experimenting with it I found it does not.  Especially not with the bosch relays I have on hand.  There is no delay between the 87 & 87a switching so the brake is the override in this setup.  I'm not sure if there is a relay that has built in delay for this feature. 

You may be right in saying this can be as simple as a trailing wiring hookup.  The dodge caravan I have has independent brake and turn signal bulbs.  I want the brake bulb to flash with the turn signal circuit.   You may have seen this in the real world, the brake bulb and turn signals are red which makes it rather difficult to see when trailing these vehicles.  Chrysler/Dodge got smart in '05 and changed it over to one bulb for both brake/turn signal operation.

Thanks for your help thus far, I will continue to research this.

While Driving to work I realized that it will not work. I thought about it all day. I took a couple of hours to analize it.

Here is what I came up with.

Blinker is hooked to the light thru the bottom relay. If the Blinker is off and the brake is hit the Relay latches to the Break circuit until you let off the break. If you turn on the blinker durring this cycle the top relay will unlatch the relay and allow the blinker to flash.

Here is the same circuit with cube relays.

Thanks hotwater,  I will play around with this tomorrow.