No dash lights

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Torkmnstr

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Ok all, here is the scoop, replaced my printed circuit board with a new one, it came with a new voltage reg as well. Bulbs are led conversions. I have 12 volts at the twist lock but for some reason it wont wont light up. I replaced the headlight switch and still no lights. The gauges have some intermitant issues, am I missing a ground or something...the cluster grounds from the two screws underneath right?
 
The cluster grounds, originally, and poorly, at the mounting screws. It is far better to add a pigtail from a ground point on the cluster and bolt it to the column support or dash frame

Here is the functional path............

The tail light circuit must be working, the headlight switch routes power from the TL fuse through the dash dimmer control (tan wire) down to the INST fuse in the panel. From there all dash lighting is distributed on orange wires. Does ANY dash light work, like the radio/ heater bezel, etc?
 
67Dart273 said:
The cluster grounds, originally, and poorly, at the mounting screws. It is far better to add a pigtail from a ground point on the cluster and bolt it to the column support or dash frame

Here is the functional path............

The tail light circuit must be working, the headlight switch routes power from the TL fuse through the dash dimmer control (tan wire) down to the INST fuse in the panel. From there all dash lighting is distributed on orange wires. Does ANY dash light work, like the radio/ heater bezel, etc?
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Heater button yes, but faint. No radio light.
 
If you are using all led bulbs, check the polarity . Led bulbs will only work in one position . Quick test, take out one of the bulbs and hold the leads from a 12 volt source to the contacts of the bulb. It will only light if the polarity is correct. That will help you identify which contact on the bulb is positive or negative.

Also, I agree with above comments about poor ground. Common cause of this problem.
 
Don't know what panel this is. Most instrument panels are made of pot metal or thin stamped sheet metal. Most screws into either material are short, threads in housings easily stripped. If its a rally panel, one of the 3 screws at center pod are the better choice.
If you plan to add a ring terminal and toothed washer at a screw that attaches the circuit board, you might need a slightly longer screw.
When I add a ground wire I put male female spade terminals in the line a few inches from the panel so my added wire will unplug like everything else, ( except the amp gauge of course ). I terminate my ground wire behind left kick panel. this so I can drop the column, take a bunch of stuff apart, retaining my ground for panel testing.
p.s. Yes there are 2 nice machine thread screws into the speedometer but rubber isolators prevent any ground path there.
 
Standard cluster, which screws would I ground from?
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AAndrews said:
If you are using all led bulbs, check the polarity . Led bulbs will only work in one position . Quick test, take out one of the bulbs and hold the leads from a 12 volt source to the contacts of the bulb. It will only light if the polarity is correct. That will help you identify which contact on the bulb is positive or negative.

Also, I agree with above comments about poor ground. Common cause of this problem.
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I know the lights work because one side came on at one point and was plenty bright...but that was short lived. lol
 
Torkmnstr said:
I know the lights work because one side came on at one point and was plenty bright...but that was short lived. lol
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Follow 67 Dart 273's instructions. He is correct. Install a ground from the metal part of the instrument cluster to the body of the car. I had a similar problem and this was the fix. Dash lights are now much brighter. I'm sure you have tried this but, just in case, take out the fuses and check them with a meter. Do not assume that because they look ok they are not blown.
 
Any of the screws that attach circuit board to housing are ground path of bulbs so any one of them could be used to attach a ground wire. So where is your noise suppression cap' mounted?
Is this a screw hole?

screw hole.jpg
 
That was the spot where it was, it’s built into the board so no need to add one per charger specialties...I guess I could ground it from there. But I should also ground the circuit screws too?
 
Torkmnstr said:
That was the spot where it was, it’s built into the board so no need to add one per charger specialties...I guess I could ground it from there. But I should also ground the circuit screws too?
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I'm going to call BS on a noise suppression cap' being built into a circuit board. Maybe you have a solid state limiter there that doesn't make electric noise. Anyway...
Just 1 well secured ground placed anywhere works. Once everything is grounded to the housing ( those screws ) the goal is ground the housing. The factories screws trough the housing into the dash are supposed to ground it but those are often pizzy little 'U' nuts on painted metal. Plus the panel isn't grounded at all until fully installed. All that the cause for adding a ground wire somewhere on the housing.
 
Yea there must be...although the radio doesn’t work any ways. Lol. Thanks if the tips all, time to ground out.
 
Torkmnstr said:
Yea there must be...although the radio doesn’t work any ways. Lol. Thanks if the tips all, time to ground out.
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Hope you isolate your problem. Let us know when you get it fixed.
 
Torkmnstr said:
Standard cluster, which screws would I ground from?
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Any of the hex head screws holding the PC board to the cluster metal casting. And as above--I spaced out. YES LEDs must be proper polarity. You will not hurt them, they simply will not light up
 
Well I grounded to each of these screws and got one side back on. The fuel gauge is working but no lights on the rest! I pulled the led out and switched it in the plug still nothing. WTF
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Actually no, I bought it with the led installed. The signals all work correct though as they aren’t led...
 
Each section of the cluster is fed power to the lights from separate pins on the PC boards. You can just look at the traces on the board and figure out where they go. Do you have a multimeter/ test lamp? How about some "clip leads?" (Alligator clip wires?) You need to "rig" it up and check it out. The dash dimmer controlled lamps are fed by orange wiring from the INST fuse in the fuse panel
 
Illumination is the orange wire. for this type inst' panel there is normally a little weld splice buried under harness tape so this wire forks to 2 separate board connectors. I wouldn't expect a problem there. Can't hurt to check that the orange wire is hot at both connectors.
I think these connectors can be attached upside down,( evenly spaced ports? ), wrong wires get on wrong posts. Check that orange wires are on the correct pins.
Bulb sockets can be the issue too. Tiny little plastic tangs hold the socket contacts against the board. The tangs of used sockets deflect or crack allowing the socket to lift.
 
67Dart273 said:
Each section of the cluster is fed power to the lights from separate pins on the PC boards. You can just look at the traces on the board and figure out where they go. Do you have a multimeter/ test lamp? How about some "clip leads?" (Alligator clip wires?) You need to "rig" it up and check it out. The dash dimmer controlled lamps are fed by orange wiring from the INST fuse in the fuse panel
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Yup! Great advice! As well, you can use a 9 volt battery with some leads attached , hook the negative lead to the cluster housing and then touch the positive lead off each of the lamp sockets and see if the led lights. This is a simple way to bench test the cluster and also isolate a break in the traces on the circuit boards. 9 volts is plenty to light the leds's
 
What AAndrews said.

I had the same problem and the old bulb sockets were cracked. I bought replacements but bench tested the cluster before I put it in. I was glad I did because I found out the contact tabs on the new sockets didn't have enough spring pressure to make a good contact with traces. I bent them out slightly and everything worked.

So, start from the socket and work back.
20190105_104342.jpg
 
RedFish said:
Illumination is the orange wire. for this type inst' panel there is normally a little weld splice buried under harness tape so this wire forks to 2 separate board connectors. I wouldn't expect a problem there. Can't hurt to check that the orange wire is hot at both connectors.
I think these connectors can be attached upside down,( evenly spaced ports? ), wrong wires get on wrong posts. Check that orange wires are on the correct pins.
Bulb sockets can be the issue too. Tiny little plastic tangs hold the socket contacts against the board. The tangs of used sockets deflect or crack allowing the socket to lift.
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Ill check those wires, I hear you on the socket. I pulled each one out and bent the tangs up to make sure they were making contact. I even pulled a working one from my buddies car and it didnt work, I think Im still chasing a grounding situation....the hunt continues
 
Well, if you look at the traces on the board(s) the screws that attach them are ground points. There should be a clean contact spot under every washer at every screw. If those are good the entire housing becomes a ground path for all. Just one added ground wire anywhere would ground the entire housing. Like the pic above of a later model panel in test bed, the one ground wire should ground all ( except the brake lamp bulb, that one bulb is routed to 2 pins/wires ).
 
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