Instrument Cluster Lights not working!

[jzak]

Hey guys,

I recently bought a 81 CJ5 , and I just found out that ALL THREE cluster lights aren't working. Everything else is working fine (Turn Signals, All 6 Indicator Lamps, Break Light, 4WD, Hi Beam). I checked the fuses and they're all good. I also changed out any missing or blown bulbs.

Unless you guys have any better suggestions, I'm thinking about cutting out the cluster light wires and splicing them into indicator lamp wires.

Thanks for any help!!

 

[Torxhead]

You might want to check and see if those bulbs are burnt out. The hot line for those lights could have a break in them.

 

[Fastatv]

Hey guys,

I recently bought a 81 CJ5 , and I just found out that ALL THREE cluster lights aren't working. Everything else is working fine (Turn Signals, All 6 Indicator Lamps, Break Light, 4WD, Hi Beam). I checked the fuses and they're all good. I also changed out any missing or blown bulbs.

Unless you guys have any better suggestions, I'm thinking about cutting out the cluster light wires and splicing them into indicator lamp wires.

Thanks for any help!!

Ensure you have a good ground when checking for the 12 volts to the lights. Have you checked to ensure you have the headlight switch ( cluster brightness ) turned all the way to the left?

 

[Hedgehog]

Also, make sure you are using the right bulbs. This won't help whether they light or not, but in the speedometer there is a blue plastic cover over the bulbs, if you use the brighter and longer bulbe they will burn and melt the blue cover. Mine had 2 out of the three covers melted.

Heres another thought. The bulbs get there ground from the fingers that hold the lights in the speedometer. On my CJ the speedometer case was a little dirty (light corrosion) and the ground through the case wasn't good. Check for this condition by pulling all or some of the lights and running a ground wire to the (cleaned) snap in fingers on the lights. If it is a ground issue the light will work. Also, this is the time to stick a cicuit tester in the socket to see if you have power. On second thought, I'd check for power first. If there's power you have a relatively simple grounding problem.

 

[jzak]

Thanks for the input! The light knob dimmer is turned to the highest level. I know this because my Indicators and Oil Pressure gauge lights are working and are also connected to the same dimmer knob.

I did have a ground problem, but my mechanic fixed it when I brought it in for an alignment.

I'm using the standard Sylvania bulbs from Autozone. They look exactly the same as the old ones and they fit fine.

I'm going to unscrew the speedo this weekend, and see whats going on back there (I've also got faulty Temp/Fuel gauges). I'll clean the snap in fingers on the lights. Maybe that'll do it!

 

[Hedgehog]

You want to use the round, ball like bulbs, NOT the longer barrel shaped ones. They both fit just fine, the longer ones are to hot.

 

[jzak]

You want to use the round, ball like bulbs, NOT the longer barrel shaped ones. They both fit just fine, the longer ones are to hot.

That's the ones i've got. Exact same shape and everything to the originals. I forgot to mention there were bulbs already installed in one or two of the cluster light sockets. The filaments weren't broken, but It still wasn't working.

 

[mtnwhlr]

Hey guys,

I recently bought a 81 CJ5 , and I just found out that ALL THREE cluster lights aren't working. Everything else is working fine All 6 Indicator Lamps,

I think they all are on the same circut, they all should have a orange wire running to them. I say this because when you dim them with your switch all of them dim so if only those three don't work either they aren't getting a good ground when installed or you have a break in the wires so they aren't getting juice. I would take a tester and first make sure you are getting power to them and if you are it is a ground problem if not I would trace them back to where you are losing the power.

 

[DHugg]

I think they all are on the same circut, they all should have a orange wire running to them.

My trouble is, after 33 years my orange wires turned yellow, the red wires turned orange, and the purple wires have faded to pink. I think I will have to rig a signal generator (a simple on-off low power fast-switching circuit called a multi-vibrator) to hook to the bulkhead connector. Once I "see" the signal on my volt meter, I'm gonna slap a "good forever" label on the wires I can verify. I don't want to have to fumble around in the nearly-dark under the dash trying to tell one faded color from another faded color ever again.

 

[jzak]

UPDATE!
So I took out the Speedo cluster from the dash, and the first thing I noticed was it's almost brand new. Not an ounce of corrosion. Looks like it came right out the box. That means I’m probably not dealing with a grounding problem.

I started going through all the cluster lights. I found out there were 4 orange-wired lights, not 3. One of the orange-wired bulbs was connected to an entirely different bundle of cables. I connected that light into the cluster and IT WORKED!! It also dimmed with the rest of the lights. I then tried the other three orange-wired lights in the cluster, and they still weren’t working.

Since I knew one wire was working, I cut off two of the non-funtioning lights, and spliced them into the working orange wire. I then put all three into the cluster sockets, and they’re working great!

The Speedo Cluster has a green tint, so it’s not as bright as the instrument lights, but at least I can see what speed I’m going at night.

I’ve still got a faulty fuel gauge, but after looking at the brand new cluster, I’m beginning to think it’s probably just a bad sending unit.

Thanks again for everybody’s help!!