tail light/brake light gremlin September 19, 2010, 08:43:37 PM I just converted my inner taillights on my 88 from the stock 194 bulbs to 3157 bulbs. When I hooked the new socket in, I just reconnected the low beam wire and ground wire back to the same wires. I spliced to high beam(turn signal/brake light) wire to the middle light's high beam wire. All that works out fine, except that when I turn on the taillights, it causes the third brake light to come on. The sockets that I spliced in had two wires for the high beam and I only connected one. They both run to the same pin in the socket, so I didn't see the need. However, if I ground that wire while the taillghts are on, it makes the brake light go off. But also if I turn on my flashers, the brake light goes off. Only problem being that when I grounded it and turned on the flasher, it blew the flasher. Which I expected. Does anyone know whats going on with this weird circuit? Quote Selected
tail light/brake light gremlin Reply #1 – September 19, 2010, 08:47:48 PM Double check that you have the new socket grounded properly.Where did you get the new sockets from ? boneyard or parts store Quote Selected
tail light/brake light gremlin Reply #2 – September 19, 2010, 08:54:28 PM came out of the tailights that I got sent. (from J/Y)As far as I can tell the ground is good I just attached it to the stock ground wire. I tried wiggling them to see if it made a difference, in fact I played with every wire, but I can't seem to fix the problem. Quote Selected
tail light/brake light gremlin Reply #3 – September 19, 2010, 09:02:41 PM HMMMMMMMMM I modified mine and had no problem , can you take a pic of your harness? Quote Selected
tail light/brake light gremlin Reply #4 – September 19, 2010, 10:16:36 PM Double check first that you spliced the running lamp ("low beam") wire from your new socket to the brown wire in the exsiting taillamp harness. Ford always uses the brown wire in it's factory harnesses for running lamps. Black is always ground. Also remove the bulbs from the new sockets and make sure the contacts inside are not shorting against each other. I am also assuming you havested these donor sockets from another Ford.If that is correct then this seems to be an unusual case of someone putting the wrong colored wire into the wrong position of your harvested donor sockets. Completely ignore the extra wire connected together with the turn/brake lamp wire. That is only there to accommodate a paralell conection to the donor car's two bulb use per taillamp to light all the turn/brake taillamp sections as designed. It sounds like to me that the donor sockets have the ground and running lamp wires reversed. The running lamp wire position on the socket as you have it is likely the actual ground position on the sockets for both "hi" and "low", not 12v+ in to "low". The black wire on the donor sockets seems to be the actual 12V+ in for the "low" circuit. Your brake/turn wire is already connected correctly. The way it is now, when the running lamps are switched on, the voltage is going backwards through the actual ground position on the bulb contact. That is why when you ground the extra brake/turn wire the brake lamps on the "hi" side light up. As soon as you step on the brake or commence a turn signal, it creates a short sending voltage from the running lamp circuit backwards into the brake/turn lamp circuit directly causing the fuse for the brake lamp or flasher to blow. Quote Selected
tail light/brake light gremlin Reply #5 – September 20, 2010, 03:58:45 PM Makes sense, but it's hooked up the way your saying it should be.Pictar:Brown wire is hooked to brown wire, black to clack, orange to whatever other color on the other harness.There was no problem before, when i only had the black and brown wires hooked up. But what you're saying does make sense, since I did change to new harnesses this time. I just really don't think they would be backwards on purpose, since it looked like they have never been touched since they were put in the original car...I'll probably just switch to the other harnesses since they are normal looking:hick: Quote Selected
tail light/brake light gremlin Reply #6 – September 20, 2010, 05:29:20 PM Quote from: sarjxxx;336160Makes sense, but it's hooked up the way your saying it should be. Pictar: Brown wire is hooked to brown wire, black to clack, orange to whatever other color on the other harness. There was no problem before, when i only had the black and brown wires hooked up. But what you're saying does make sense, since I did change to new harnesses this time. I just really don't think they would be backwards on purpose, since it looked like they have never been touched since they were put in the original car... I'll probably just switch to the other harnesses since they are normal looking:hick: Well, the socket in the picture looks correct with the pin positions in the right places. That is strange. Wish I was there with you I could better help you figure it all out. Some simple tests with a multimeter would show what exactly is going on. Quote Selected
tail light/brake light gremlin Reply #7 – September 20, 2010, 06:06:09 PM oh yeah, and here's whats really interesting. I forgot to mention this before.I was thinking maybe it was a result of the LED's that I was using, so I pulled the bulb out. But, that had no effect. So this means it's doing it without closing the circuit via the bulb. Hmmm...I'm just gonna switch int the other sockets and see what happens.. Quote Selected
tail light/brake light gremlin Reply #8 – September 21, 2010, 02:18:13 AM Quote from: sarjxxx;336169oh yeah, and here's whats really interesting. I forgot to mention this before. I was thinking maybe it was a result of the LED's that I was using, so I pulled the bulb out. But, that had no effect. So this means it's doing it without closing the circuit via the bulb. Hmmm... I'm just gonna switch int the other sockets and see what happens.. Do the sockets work correctly with regular bulbs installed instead of LED's? Quote Selected
tail light/brake light gremlin Reply #9 – September 25, 2010, 10:39:23 AM Ohh... kaaayy.... So, apparently after I changed the blown fuse after grounding them out, the problem has maaagically corrected itself. WTF????? Oh well at least they work right now. Quote Selected
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