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blinking instrument lights?

I would get an updated electronic voltage regulator. Did that on my '66 and it made a world of difference and there was nothing wring with the original one.
 
"AzPete" said:
I would get an updated electronic voltage regulator. Did that on my '66 and it made a world of difference and there was nothing wring with the original one.
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Now that you mention it, I do have one of those.
 
Well, as you might remember, the turn signal eventually fried. I replaced it. I also put the stock crank pulley back on to speed up the ALT at idle. I added a ground to the tail lights. I still have the problem. I have added a fan relay today along with a temp switch. Everything else seems to work fine, this one is really got me stumped. :expl
 
Is there a difference with the engine running or with it not running and just the key on to get things working?
 
well I just went and sat in it, with the engine off. It still does it, I can hear what sounds like the instrument voltage regulator making noise then the lights go off. It doesn't do it right away, like it has to get hot. It will also do the same thing with the lights off, with the garage door shut I can see the brake lights start to flicker and I hear the same sound. It sounds like its coming from behind the insturment panel.
 
Do you have an IVR or do you have after market gauges? If still have an IVR, replace it or build the electronic one that has been mentioned somewhere on here or VMF. I am thinking it has an internal ground problem.
 
I still have factory type gauges. I added a factory tach and oil pressure gauge where the clock was. I also have a new (stock) IVR. I'll look into building an electronic IVR. How would that be related to the brake lights?
72_08_03_09_2_00_45.jpg
 
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I am thinking just an overload on the system if the IVR is bad. Does that wiring have any circuit breakers in it or any fuseable links? I doubt it but I am not sure.
 
Try removing/disconnecting all but one bulb on each tail light. See if that makes a difference. Also, if you have a set of stock tail lights, hook them up with a good ground and see what you get there.

Also, on the brake lights you use, could there be a need for a different brake light switch. Maybe a heavy duty for that option?

Better fix this soon or you just may have to sell me the car for parts..... :toot It isn't worth driving this way......
 
Craig,

Are you using the dynamite sticks (or the newr equivalant) to fire the taillights/brakelights? As I remember wiring my sons sequentials, the sticks needed to have a dedicated 12 volt (switched) power source... I assume that otherwise the sequentials would overload the system.
 
"AzPete" said:
Better fix this soon or you just may have to sell me the car for parts..... :toot It isn't worth driving this way......
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:rofl

Dave, yes I do have sequential turn signals. The wiring diagrahm didn't specify a dedicated 12v power source but they may not have considered using these on older cars. Can I wire up some relay's on the brake lights like the headlights? If so will it effect turn signals?
 
You should be able to do relays before the turn signal switch without problems. Just come off the brake light switch wiring.
 
okay, I'm not the best when it comes to wiring. So let me get this straight. If I run a dedicated 12V to the brake light switch for power and use the brake light switch to trigger the relay, it should work okay?
 
"daveSanborn" said:
I've got the Scott Drake wiring schematics for wiring up their "new" dynamite sticks. Would they help you?
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Couldn't hurt I guess. Thanks
Here are my high/low beam relays and fan relay as well as my junction block.
72_10_03_09_5_12_08_1.jpg
72_10_03_09_5_12_07_0.jpg
 
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Okay, so I took out the extra two bulbs per side in the tail lights and I had no blinking/intermitten on/off issues as with all 6 bulbs installed and brakes on. It would seem that the extra bulbs (load) are the problem. I didn't unhook the sequential units, just took the bulbs out. What troubles me is the 67/68 Cougar uses the same turn signal (TS) switch as the Mustang. If the TS switch is the same, and all I did was add 67 Cougar tail lights, why wouldn't the Mustang TS switch work fine? Well, I looked in my 67 Cougar, Fairlane, Falcon, Mustang shop manual at the wiring diagrams for the Cougar and low and behold the Cougar has a much more complicated set-up. Besides the sequential unit itself, the Cougar system has an emergancy flasher relay and a TS indicator relay and a TS relay which the Mustangs do not. Can't see a brake relay but there is a lot of stuff the Mustang doesn't have that the Cougar does. Anyway, I think by adding a relay to each brake light lead, the TS switch will only be a switch and not have to deal with the load of all the bulbs going thru the switch. The TS's don't stay on long enough (IMO) to need a relay but I might add relays to them anyway. I still don't understand why the instrument lights blinked off when the brake lights were going off but I'm hoping this will fix it before I fry this TS switch too...
I'm also courious why I haven't heard any of the Eleanor guys have the same problem unless it is that they are using all new wiring harness and LED lights and stuff like that. Oh well, hope this works.
 
I would bet that once you do the relays, things will work better. Just be sure to run heavy enough wire to power the relay operated system or you could have the same problem.
 
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