Instrument cluster ground

[Vineyard86manch]

I’ve been having an issue with my instrument cluster when my headlights are on. Every instrument except the speedometer stops working, and the blinker signals and high beam light stay on unless engaged. When it first started doing this it would correct itself after a few minutes of driving but now it’s all the time. I’ve been told the ground is somewhere near the parking brake assembly? Pics or words of guidance please🙏🏻

[Ωhm]

Instrument Cluster (IC) has two (2) grounding points. C102 & C103. C102 pigtails out near the bottom of the steering column. C103 is under the hood on the middle left side of fender. If grounds are good, check C203 where it connects to the IC, could be loose.

 

[gogmorgo]

Cruiser54.com, one of his tips addresses the dash ground. 

I'd give the headlight switch a look if that doesn't help. I can't really see it causing anything more on the dash than just turning on dash lights if it goes bad, but it's also a known weak point that likes to melt harnesses. 

[Vineyard86manch]

Thank you both for your insight I’ll see what I can figure out!

[cruiser54]

CRUISER'S MOSTLY RENIX TIPS

IMPROVING THE INSTRUMENT PANEL GROUND

NOVEMBER 17, 2015 SALAD 13 COMMENTS

 

The ground point for the complete instrument cluster on your XJ or MJ is located up under the driver’s side dash. If you lay on your back and look up under there with a flashlight, without wearing a hat, you will see a black wire attached to a shiny piece of metal almost directly above the hood release knob. The screw will have either a ¼” or 5/16″ head on it.

This ground point is responsible for handling the ground circuit for the following items: Dome lamps, seat belt and key warnings, transmission power/comfort switch, wiper switch, headlamp switch and delay module, fog lamp switch, cargo lamp switch, all instrument panel grounds and illumination, power windows and door locks, cruise control dump valve, and a few more things.

The problem is that where the ground point is located does not share good contact with the chassis where the ground should be. The solution is simple:

• Make up a jumper wire with #10 gauge wire about 10″ long. On one end, crimp on a ¼” round wire terminal. On the other end, crimp on a 3/8″ round wire terminal.
•  
• Remove the screw from the existing ground wire and attach the small terminal of your jumper so that the original wire and your new jumper share the same attaching point, one over the other.
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• Look above the driver’s side plastic kick panel just forward of the top of the hood release knob. You will see an 8mm stud there. Attach the large terminal end there with a washer and nut over it tightened securely. Use a coating of OxGard at all ground contact surfaces when attaching the screw and nut.

**Special note for Comanche owners: Make your jumper wire 12″ long and attach it on the driver’s side kick panel close to the fusebox on the 8mm stud.**