Dash lighting - Stumped

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Joined
May 19, 2021
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Location
Between Fort Mohave, AZ & So Cal (Upland)
My Car
73 Grande will undergo three phase build process. Phase 1 is complete (driver). Phase 2 is interior/exterior restoration. Phase 3 is ++ performance.
Ok, what I know: new NPD headlight and turn signal switches, replaced all of the dash lights with new, tested, incandescent 194 bulbs, a new NPD ribbon circuit board, have 12v at the LtB/R wire exiting the headlight switch, fuse 3 is good (tested), and when I turn the headlight switch to either running lights or headlights, this is what I get from by instrument cluster:

IMG_2344.jpeg

I‘ve got zero dash lights.
 
Ok, more info. I don't know if I ever had dash lights since this was a car from a salvage lot and it was missing too many pieces to mention. I removed the instrument cluster so I could install the replacement tack for Clock kit from rocketman. WhI’ll I was in there, I decided to replace the ribbon cable and replace every bullet with a good known 194. I cleaned the connector for the ribbon wire thoroughly and installed it. There isn’t any way to put it in backwards is there? As you can see, I have both turn signals light, but that does not use the same circuit as the dash lights (19). I have two or three electrical diagrams, schematics, so, I’ve poured over them with no answer.
 
I thought I would remove the new instrument cluster, take pics of the back of it, and post those, as well as the 73 color wiring diagram of the cluster:

IMG_2345.jpegIMG_2346.jpegIMG_0979.jpeg
 
Ok, I’m an idiot.

Thats all I really needed to write, but I feel like explaining my idiotness might help someone, someday, to avoid it.

Sure, I connected everything as it should be, it wasn’t so bright in my garage, and from the front, I saw nothing. NOTHING, how could that be. I double checked everything, tested each bulb, replaced the ribbon, headlight and turn signal switches, so I would have no worries; I saw nothing.

So, after doing my due diligence, checked for power at the headlight switch, ok good; I had a good ground, fuel gauge moved to 1/4 tank, that’s right, wiggled stuff; I saw nothing.

So I reached out to the community, read off the facts, etc. Then, 71fast, who was in a conversation with me, asked a few, logical questions. I checked those things, nope, still nothing wrong. So, I removed the instrument cluster for the 4th time, sat it on my bench, and using my power probe, simulated the power, which I assumed I didn’t have, to test the dash lights. Well, I couldn’t hold my two hands to hold the probe on and see the front, so I had the wife look at the front, while I did the power. She said, “I see Nothing.”, but I, looking from the back, see some signs of light life.

This is my 2014 F150 dash in day light:

IMG_2351.jpeg

My memory isn’t what it use to be. I’m never gonna have that with my stock 73 dash, and I forgot that. Now, I did have two bulbs that would not light. Turns out you have to clean each of those bulb sockets and contacts to assure you’ll get light out of them. Now, all 7 lights illuminate the dash, and I can barely see that in the semi darkness of the garage. I’ll test it tonight, pitch black conditions.

So, sorry to raise a ruckus when all along it was me. Steve
 
Glad you figured it out. I recommend pulling the gauge housings apart and spraying the interior with gloss white paint. It makes all the difference in gauge lighting. If any of the blue diffusors are melted, those need to be replaced as well. You could also replace the factory 194 bulbs with some that have a few more candlepower, but you quickly get into too much heat.
 
All great ideas. I did do the paint and verified I have good blue diffusers. I got up before the sun this morning to verify I could actually see the dash in the dark, and I could. It’s no 2014 F150, but it’s ok. Am I right that if I just change those 7 194’s to LED, I don’t have to make any other systematic changes? And doing that will not induce more heat?
 
Steve, I know full well what you've gone through. For me , anything electrical becomes a nightmare.
However, I'm glad you were able to push through and solve the problem.
Now, before you put it all back in your car, I highly recommend and suggest you contact Bill at HiPoParts (www.hipoparts.com) and treat your car and your eyes to a set of his Elite Series II LED bulbs ( he sells 2 types, you need the brightest).
There are cheaper LED's on e-pay, BUT you get what you pay for, believe me. One more thing, if you go to LED dash lights, you MUST leave an incandescent bulb in the ALT socket.
Then while you're in there, add LED headlights with relays (preferred). You've read my posts I'm sure on the Hella brand lamps, fitted with Sealight LED bulbs with the added water shields. By using relays on the headlights, the interior lights ought to be quite a bit brighter too. That is what I noticed on my car because the headlights are being powered directly off the battery/alternator.
Anyway, whatever you decide, so glad you've figured out the problem and no, you're not an idiot, you're just human.
 
Thanks Stanglover. I purchased a set of LED bulbs early last year when a friend who has a 72 Mach 1 told me it was a necessary upgrade. I don’t remember where I got them, maybe CJ or NPD. I wanted to make sure the stock setup worked first, on my 73, I’ve got that instrument cluster that uses a separate harness for the Alt bulb, not the ribbon circuit. So, I know it needs the resistance of the bulb to work. I’m going to test the LEDs to see how they look.
 
Thanks Stanglover. I purchased a set of LED bulbs early last year when a friend who has a 72 Mach 1 told me it was a necessary upgrade. I don’t remember where I got them, maybe CJ or NPD. I wanted to make sure the stock setup worked first, on my 73, I’ve got that instrument cluster that uses a separate harness for the Alt bulb, not the ribbon circuit. So, I know it needs the resistance of the bulb to work. I’m going to test the LEDs to see how they look.
Sounds good Steve. You have it under control then.
 
Stanglover, that’s what this guy thought moments before . . .

View attachment 76376

Sad and somehow likely true at the same time.
Sad indeed Steve. That's one bent up car. And you're right, we always seem to think everything will be all right........... till it's not.
 

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