Improving the Instrument Panel Ground


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.
  • 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.

IP ground location

**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.**

29 thoughts on “Improving the Instrument Panel Ground”

  1. 1990 XJ removed the aforementioned ground wire in hopes this was issue with my weak power locks, once removed, they still worked weakly, power windows still operated fine, dome lights still workec. This ground wire evidently is not the ground for these items

  2. Hello Cruiser. I found my way here from the NAXJA forum. I have a stock 1993 XJ 4.0 (so not a Renix…) and am trying to solve an electrical problem or two. The hazard flasher lights don’t work, although the turn-indicators do. All the bulbs are good, and I’ve checked and cleaned all the bulb-fittings.

    I have tried two – new – replacements for the hazard-flasher unit (it was a Wagner 224). One is thermal, the other electro-mechanical. Neither works. Initially they made the hazards flash sporadically, now the hazards simply don’t flash at all.

    I’m thinking it may be a bad ground connection (which is how I arrived on your site!). But exactly which ground connections should I check – there are more than just the one by the fusebox/kick panel.

    Another problem which may or may not be relevant: the dash instruments all work fine, except that the speedo needle has a mind of its own. Sometimes doesn’t move at all, sometimes wakes up after 15 minutes driving, often reads 30mph too high, sometimes revolves clockwise back to zero. Is this another sign of a bad ground somewhere?

    1. Find every ground in your engine bay and refresh it.

      Do you have a trailer harness?

      You aware of the taillight and fuel pump ground behind the panel that’s behind the spare tire, right?

      1. Ok, will do – assuming I can find all those ground connections in the engine bay!
        I don’t have a trailer harness, by the way…
        I’ll try to find that tail-light and fuel pump ground connection at the back as well.
        But the key question (surely…) is where EXACTLY is the ground connection that serves the turn/hazard circuits? It’s labelled as ground connection “I” in the XJ wiring diagrams, and is said to be on the “left side shield”. There’s also connection “J” on the “right side kick panel”. But I’m danged if I can find either of these. I need a picture or diagram with an arrow on it to show these locations.

  3. Every engine bay ground is in plain sight. Black wires with sheet metal screw going to body.

    Remove the spare tire and the panel behind it. Fuel pump and lighting ground is there. Black wire with sheet metal screw.

    Do the instrument panel ground upgrade.

    1. Thanks – have been able to see and identify all the ground connections in the engine bay, and have “refreshed” them all.

      Also found and cleaned up the one behind the spare tyre – which was in fact clean and uncorroded.

      Having hung upside down in the driver’s seat, twisted my neck through 180 degrees, banged my head on the brake pedal and fought my way through a tangle of wires, I can see (with one eye!) where the ground connection is behind and below the instrument panel. Looks as if access to clean it up – and/or to do the suggested upgrade – requires removal of the plastic panels below the dash and steering wheel. A job for another day.

      Meanwhile, mystery solved with the turn/hazard flasher units. I thought the turn flasher relay was faulty, and the hazard one was good. Turned out to be the other way round. They seem to be interconnected (one won’t work without the other). Replaced the hazard flasher unit, and both circuits now work fine!

      Mystery over the weird behaviour of the speedo needle remains…

  4. No steering wheel removal needed.

    That instrument panel ground is important to upgrade.

    The wobbly speedo needle was provided from the factory at no extra charge….LOL. The routing wasn’t optimal for sure. You can lube the cables and hope for improvement.

  5. Is this ground responsible for the power seat controls as well? It improved the function of the locks and windows, but still no control of the seats. I had intermittent control of the seats at first, but now they are dead, so I suspect ground issues. Still in the process of improving grounds, but as of now the behavior is this:

    No control of right rear window, left rear window can be controlled from the drivers seat, but will only roll up from left rear door. Front windows operate fine. The window functions have improved since doing this tip and adding a #4 gauge wire between the negative battery bolt and radiator support, so I believe the rest of the window functions are due to grounding issues as well?

    Don’t care so much about power locks, but windows and seats are my priority as far as power functions. Thanks!

  6. I don’t have a diagram at my fingertips right now, but I’m pretty sure the power seats are on their own. Check the plugs and switches. Contact cleaner is your friend.

    Same with window and lock controls in the doors. Contact cleaner. And checking the wires from door to body for breaks.

  7. Cleaned all the seat connections, and although some were corroded, still no luck. Fairly happy with the windows for now, but If you happen to come across the seat ground location I’d love to know it as the seat is stuck in a bad position.

  8. My fuel gauge calibration appears to have changed. I own a 1988 Xj Limited w/the Highline analog gauge package (?). Fuel, engine temperature, oil pressure, and battery voltage are featured with larger tachometer and speedometer. All gauges work fine but I noticed the fuel gauge indicates more fuel is consumed than is the case.

    For example, yesterday I had ~ 2 hours remaining in a drive to go fishing and noticed the gauge displayed ~ 1/2 tank. This did not seem correct given that I left the house with a full tank, a few miles on the trip meter, and had completed a 1 hour drive to pick up some supplies for the trip. To my surprise, the tank would only accept 5.2 gal of fuel. This is not a consistent amount of fuel with a gauge reading of just over half a tank. My experience with this Xj demonstrates 5 gal corresponds to a gauge reading of ~ 3/4 tank remaining.

    Maybe the fuel pump ground behind the spare tire panel? If this turns out to be the fuel pump I must also replace the fuel filter and ballast resistor because its resistance has decrease with age.

  9. I just upgraded all my interior and dash bulbs to LED. The dash lights worked for a week or 2, then stopped. As soon as you turn on the parking lights or headlights, fuse #10 blows. I have replaced the headlight switch with a new one after this starting happening…..didn’t fix it.

    This is a 94 XJ. Every other light works including turn signals.

          1. Ok….sounds like I have some wire tracing to do in my near future.
            Can you point me to the wiring diagram that I should be using to track down the pinched or bare wire?? It is a 94 XJ Sport 4×4 manual transmission 4DR.

  10. Hey, I’m having some real trouble finding this instrument panel ground. I feel like the PO might have removed it (lots of fuck shit in this Jeep). Any chance you could provide an image of what it’s supposed to look like?

    1. Well, if they did, numerous things would not work at all. Absolute bottom edge of the dash panel between steering column and driver’s door.

  11. How about a 2000 XJ with the “no bus” message at odometer and no gauges working. P1698 code. Unplugged instrument cluster, had the dash out ,changed the TCU module. At a loss . Truck runs just no gauges.

  12. Hello I was trying to ground a switch with a built in light at this location without disconnecting the battery and ended up burning a fuse. After replacing the fuse and not hooking up the light built into my switch, the jeep stars and runs fine but the gauge cluster is completely not responsive.

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