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Gauge lights

R

RustyRed

Active Member
I am running LED bulbs in my gauge lights, they are brighter and the old stock style ones were so dim I couldn't see jack at night.

When I was putting my harness back in, one of my bulbs had the "knobs" (for want of a better term) on the side worn down so it wouldn't stay put in the socket. I can't recall if I left it empty or put an old stock style bulb in there temporarily...at any rate my knew set of LED bulbs came in so I am going to put them in this weekend.

Can one bulb keep all the gauge lights from coming on or should I be checking for something else like a bad voltage regulator, bad switch or bad ground somewhere, etc? I was assuming one bulb wouldn't knock them all out of commission but figured it's worth asking.

All the other lights work so it's just the gauge lights.

And Dave, I am pretty sure this isn't related to the timing... :)
 
I was thinking that was the case but figured it couldn't hurt to ask.

What are some likely issues to check?

I was planning to start with the obvious things like double check how the harness is wired, check around for ground wires with issues, etc.

How would you know if your voltage regulator on the back of the gauge cluster was bad or not though? The light switch is fairly new...about a year old.

My hunch is I may have just hooked something up wrong or missed a ground somewhere, etc.
 
In general, LEDs are very voltage sensitive - so grounds, low volts from the switch, bad connetions, etc can stop them from lighting (where a regular bulb would be a dim glow).

The guage cluster (instrument) regulator doesn't affect the bulbs, they run off 12 volts.
 
"apollard" said:
In general, LEDs are very voltage sensitive - so grounds, low volts from the switch, bad connetions, etc can stop them from lighting (where a regular bulb would be a dim glow).

The guage cluster (instrument) regulator doesn't affect the bulbs, they run off 12 volts.
Click to expand...

Thanks, that helps narrow down the search some and makes sense....
 
Ford put in a large splice in the main harness, where 3,4 or 5 lines come out for dash lamps. I've run across harnesses where one line coming out of the splice is bad with high resistance. I had to replace the entire splice or splice that line into another, good, line.

Check to see if you have voltage by removing the bulb and checking the bulb contact pin relative to a good grounding point. If you have voltage, it may be the bulb or bulb socket; if you don't have voltage, the line is bad. Then check another bulb contact pin to confirm that you have voltage going to the whole system.
 
I'll check it Mid.

Worked before I took it out so hoping it's just a bad fuse or maybe I forgot to attach a ground, or something along those lines. I'll probably also check where it plugs to the light switch just to eliminate things.
 
the instrument lights do have their own fuse which is a little one. Hopefully it's that simple...
 
"tarafied1" said:
the instrument lights do have their own fuse which is a little one. Hopefully it's that simple...
Click to expand...

Any idea which fuse?

I haven't had a chance to look at it as yet. I was going to look at it yesterday afternoon when we got back for the Children's Museum but got side tracked with other projects around the house plus a couple of the boys' friends coming over.

But I did happen to think that the lights for the turn signals work...not sure if they are on a different deal though...I'll get a round to it one of these days but on the plus I can drive it as is since I don't drive it very often at night.
 
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