Dim gauges

[demesauce]

So I am having an issue with the gauge cluster illumination and need some advise. The black lights on my gauge is super dim, basically non existent. No change when twisting the light knob. I don't think it's a grounding issue because the green turn indicators and blue high beam indicator shine bright. I also have my backlight for the tach spliced into the gauge lighting, and that is super dim too (and doesn't use/need the same grounding as the gauge cluster). So could it be the actual headlight switch? Is there an easy way to test my assumption?

Thanks in advance

 

[Rustytruck]

check the voltage at the gauge light. the headlight switch has a coil resistor on the back when my resistor burned through taking all the dash light power from the lights instead of replacing the switch I just soldered a jump wire on the resistor so I always have full power. I always liked full power anyway.

 

[1970 Palmer]

X2 on what Rusty said.

Make sure you have the instrument panel ground wire attached to the back panel.

Make sure the ground wire has a good ground. You can use a multi meter, or even a clip on test ground wire.

Without a good ground, the current tries to seek a ground through the path of least resistance, and the bulbs will be very dim.

John

 

[DirtDonk]

There aren't many illumination bulbs either, so make sure they're all (all three?) still working. As said, check the voltage at the sockets. And yes make sure that the grounding is good.
Since the bulbs in a stock setup all ground through their contact with the cluster, the cluster has to be well grounded to the dash, which has to be well grounded to the body, which has to be well grounded to the battery.
Your assessment that the turn signal indicators being bright indicates a good ground is sound. But the individual sockets can still lose their level of grounding due to either lack of spring pressure when the clips weaken with age, and/or corrosion buildup.

You might even reach back there and twist the sockets by hand while the lights are on to see if the brightness changes. Worth a shot.

As you said, headlight switches get old too. Might come down to that, but obviously there are multiple things to check

Good luck.

Paul

 

[JeepGoneBronco]

Figured I’d provide some closure on this thread. Had the exact issue as @demesauce . I swapped my bronco’s harness with painless harness and had no gauge lights or dash label lights. I didn’t have them before the swap either, but after reading forum after forum of @DirtDonk ‘s love of grounds, I too have become a believer of lack’o grounds. Grounded my engine to frame, frame to firewall and firewall to dash, but still no gauge lights. I ran a clip on wire from my dash ground bolt to the ground casing of one of the gauge light bulbs and sure enough they all lit up like Christmas.

 

[DirtDonk]

That’s great! Glad to hear something finally worked. Especially after all the work you went to to install a brand new harness!
Usually, that’s not as big an Issue with aftermarket harnesses because they typically have dedicated grounds for the dash lights.
Maybe Painless has modified the way they worked that.