tail light flash with turn signal

They will have to be SPDT relaysKevin Pierson

KPierson wrote: If my above assessment is correct try this: Relay 1: (alternating relay) Pin 85 - ground Pin 86 - turn signal bulb wire Pin 87A - marker light feed wire Pin 30 - marker light Pin 87 - To relay 2 pin 87A How it works - The relay energizes each time the turn signal bulb lights up and breaks the voltage to the marker light. This causes the marker light to cut out each time the turn signal turns on (causing them to alternate). Relay 2: (turn signal / marker light together) Pin 85 - ground Pin 86 - marker light feed wire Pin 87A - from Relay 1 pin 87 Pin 30 - out to marker light How it works - If the lights are off the relay is deenergized. This allows the voltage from the parking light circuit to pass through relay 2 and power the marker lights. If the lights turn on the relay energizes and no longer allows the turn signal to power the marker lights. Check all local laws and restrictions before making these modifications. Also, use your best judgement when hooking this up - I've never tested it and it may not work. I would start with Relay 1 and get it working before adding relay 2. You'll need two relays per side (4 total). Lastly, I'm not sure how much current any of these lights take. Make sure the turn signal circuit supplies enough current to power the marker light at the same time. An additional relay and fused power supply may be needed to make sure there are no excessive current draws that could damage the vehicle.

  Ok I just reread this after having a much deserved sleep and I just wnt to make sure on a few things. I am figuring that I have to cut my marker light wire correct? Also on relay 1 you have the mark light wire going to 87A for feed and 30 for the light. Then on relay 2 you also have the marker light wire going to it 86 for feed and 30 to light. I guess that confused me a bit. will I have to run from 87A on relay 1 to 86 on relay to from the feed and the out to the light from 30 on both relays?

Sorry for the doumb question but I just want to make sure I do your wire up justice.. Thanks again for the help.

Yes, you will have to cut the marker wire on both sides. Once you cut the wire, connect each side to both relays as instructed above. Have you already purchased the relays? I would advise getting some relays that have harnesses attached to them. You could then prewire most of the relays out of the car and only have a few connections in the car (ground, parking light, marker feed, and marker light). If you need a source let me know - I have plenty of relays and harnesses laying around.Kevin Pierson

 I have not purchased them yet. Went out today but the radio shack around ere did not have what I needed. I think I need to go online and order some.

Sorry for hijacking bump... But FYI to my 2nd replay (reply ~#11 on page 1), the JFET has a failing - it's need for opposite polarity supplies. I still want to pursue that path (whether JFET or other devices), but just letting anyone interested know that it wasn't that simple. (I didn't think so, I think I went down every avenue eons ago... But it's always nice to recheck old work - it's better than admitting forgetfulness.) I'll update my progress - probably in ~10 years.