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Discussion Starter #1
Hope someone can help on this one. The brake lights on my Shelby have acting strange lately. The brake lights seem to be operating just fine untill I turn on the headlights. Then the brake light filaments of the rear bulbs gets dim on the inboard light and gets progressively dimmer as is goes outboard. So much so that the last bulb barely lights up at all. With the lens in place, the brake lights are non-existant. I've tried an NOS headlight switch and it actually got worse. While testing with a meter, I discovered that by messing with the grounding of the housing, the bulbs got alot brighter. So the real question is, how can I re-ground the light system to make the lights work correctly. Thanks for any insight on this.
 

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Discussion Starter #3
It's a new strap. But I will check it again. It's the headlight being on that really causes me concern. I'm afraid to take it out at night due to this problem.
 

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The old 65 t-bird housings are famous for this. First make sure the ground strap from the tail light harness is well grounded to the housing though thats not the most likely culprit. As you have discovered by your wiggling, the problem is typically caused by corrosion between the brass bulb holder and the aluminum housing.(remember high school chemistry about dissimilar metals?) The drag is on a 68 you need to remove the rear bumper and tail light panel to work on them. Secure the housing and place something like a scrap of wood against bulb holder from the bulb side and give it a good rap with a hammer. The holder should pop out.Once its out clean the outside of the bulb holder with some 220 sandpaper. A 3/4" plumbers pipe brush works great for the inside of the housing. While you've got them apart redoing the reflective paint on inside of housing will make bulbs shine a lot brighter. Press the holders back into housing and make sure it is fully seated. I like to put a little dielectic grease on the outside of bulb holder. If the holders aren't snug you will need new harnesses and possibly housings. Pete Disher has new harnesses, I should have several sets of housings around. Good luck.
 

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Discussion Starter #5
Thanks tlea! I'll give it a shot this week and let you know what happens. Your right about it being a drag to have to disassemble the rear end but it's better than getting rear ended! :: Would the dynamite sticks have anything to do with this? Mine are obviously early repros. I was thinking of getting a set from Pete. What do you think?
 

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My experience with dynamite sticks is they typically either work or they don't. I think you said yours are flashing but weak.More likely a ground. Pete has the correct sticks with the plugs as does Cougars Unlimited, I highly recommend their electronic flashers, nice strong signal and slows it down the way it should be.
http://www.thuntek.net/cougars_unlimited/Catalog_retail.PDF
 

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Discussion Starter #7
tlea,

It's just the brake lights that are dim. The turn signals seem to be ok. And it only occurs when the headlights are on. When the headlights are off, the lights seem to be fine. When their on, the brake light bulb filament lights about 1/2 power on the inboard buld and gets progressively dimmer as they go outward. My wiring is a bit cobbled. I believe my car may have been a sequential delete car that was originally shipped to California and converted when the car went up to Washington State for about 5 years. So I'm thinking maybe I should just start fresh back there. Are the ones Pete sells "electronic" like Cougars Unlimited? Does his need the flasher as well? Thanks for all your help on this. I've been messing with this for about 6 months and your the first person that has actually understood or had a clue what I was talking about or how to fix it. This forum rocks! :D
 

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1st of all reguardless of whether or not the delete was used the same plug should be there. Either the delete plug or dynamite sticks plug into it. The other unattached wire gets quick-connected to the tail light harness (if you want to be concours correct, Shelby used white scotchlocks). I always tell people the first place to start is with the wiring and grounding. If any is suspect, get rid of it. Alloy finally is producing the housing harnesses (these are the ones Pete sells) and they are exact. As far as the flashers(not sequencers) I don't think Pete has them. I'm pretty sure he uses the original type can flasher. I've found that the electronic ones are superior and give a much better signal. The circuit however when braking does not go through the flasher but does go through the sequencer. Because you are asking the lights to do more in quicker amount of time when braking I think a bad ground would be more evident. Having said all that could it be the sequencer? Sure but I'd still start with the wiring. If you want PM or email me so this thread doesn't get to buried. I have wiring diagrams and pictures. The sequential tail lights are one of my favorite things about the 68 and very rarely do I see cars with them working properly.
 
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