82 jeep scrambler dash lights help

[Lopaka55]

Hey all. Got an 82 scrambler rebuilding from the ground up. Bought a painless wiring harness pre-terminated got everything working except for dash lights and speedo illumination lights. Called painless support and they didn’t seem to be much help. I’ve got all my grounds hooked up and showing good ground. I’ve ground the dash with extra grounding strap as well. They seems to maybe think it was my headlight switch causing the problem got a brand new one and still no go. Any help/ideas would be very much appreciated!

 

[Manic Mechanic]

Are you using LED lights in the dash? If so turn them around LEDs only work in one direction where as the old lights worked no matter what.

If you're still using old style bulbs I'm not sure could be a bad fuse

Sent from my E7110 using Tapatalk

 

[Lopaka55]

Yeah not using LED just the normal bulbs. Thank you for the suggestion though

 

[CJ]

How are you checking? Do you have a meter or a Power Probe? Do you have a TSM?

1982 Complete Technical Service Manual - CJ5 CJ7 CJ8 Cherokee Wagoneer Truck

1982 Complete Technical Service Manual - CJ5 CJ7 CJ8 Cherokee Wagoneer Truck

jeep-cj.com

 

[Lopaka55]

Using a multi meter and power probe.

 

[CJ]

How far back are you feeding +12v before the dash lights do not work?
How does the harness check against the TSM?
You have some good equipment (Power Probe) so it sounds like you have a good grasp of low voltage wiring.

 

[j6824]

Probably a long shot, but you might try turning the bezel of the headlight switch all the way to the right...has a rheostat dimmer in it that will take them down to off as it's turned to the left

 

[Kingofwood]

had the same prob on my 81 CJ5. I changed switch out and still no fix. changed out hi lo switch on floor bingo it all worked. Thats with a new painless harness.

 

[Lopaka55]

That’s the weird part I’ve got no voltage at all for the orange wires that control any illumination. I’ve got it coming into the switch on the 3 red wires just nothing going back out to the orange and it’s brand new switch unless there’s something wrong with it from the factory? Possibly? Yeah I’ve turned the switch both ways and nothing there either unfortunately. Also have a brand new floor switch so seems like that wouldn’t be the problem on mine either. Thank you all for suggestions though

 

[Kingofwood]

Do you have an inline fuse that goes from light switch to dash lights. I have one on mine, I blew it once while hooking up a gas gauge. Took me awhile to figure it out

 

[CJ]

That’s the weird part I’ve got no voltage at all for the orange wires that control any illumination. I’ve got it coming into the switch on the 3 red wires just nothing going back out to the orange and it’s brand new switch unless there’s something wrong with it from the factory? Possibly? Yeah I’ve turned the switch both ways and nothing there either unfortunately. Also have a brand new floor switch so seems like that wouldn’t be the problem on mine either. Thank you all for suggestions though

If you back feed +12v to the orange (#11) wire with the Power Probe do the dash lights illuminate?
Using your meter on ohms with no wires connected to the H/L switch, what resistance do you have from tab / connection 11C and 9B as you rotate the dimmer from off to full on. Check 11C and 9B to H/L switch metal body also. Does the resistance change?



The confusing part off the instrument illumination is how the rheostat works to ground. See the red arrow below.