troop1

'91 cherokee 4.0l. My speedo, tach and fuel gauge all stopped working at once. Went the wrecking yard and replaced I/P cluster and got the same results. ???? I'm stumped. I know everything goes through the ECM, but I was hoping someone has fixed this before.

freegdr

aint the speedo cable operated?

radio flyer

Check the ground wires on the block behind the dipstick. speedo is electronic.

freegdr

dont think they started till 93? yep list a speed sensor

lewphelps

RadioFlyer, thanks for posting the photo showing exactly where the ground wires are connected to the motor block. They're hard to find even when you know what you're looking for.

I just bought a 95 Cherokee Sport with 3 inch lift band 31 x 10.5 Falken tires. The speedo/tach/odo/gas gauge failure came with the rig. There were a lot of forums that discussed the problem, but this is the only place I found not only the correct description of the fix but photos as well.

If you look at the electrical circuit diagram for the instrument cluster,(it's in the FSM) it's pretty obvious that the problem has to be the ground wire. The instruments that are affected all share one ground wire. Other instruments on the same cluster have a different ground wire, and they all have the same +12VDC power supply. If the fault were anywhere else, a different combination of non-functioning instruments would show.

krazynezz

Thread jacking for a second.. . What would cause an electric speedo to wrap backwards most of the time, some times not work at all or very occasionally work properly? When it decides to work its usually after hitting a sizable Bump or some times thumping the dash will do it. 93 Cherokee sport 4.0

All other gauges function properly

prerunner1982

The plug on the back of the gauge cluster is also known for messing up. Clean it and put some dielectric grease and see if that helps. I typically open mine up about once a year as I have problems with speedo and tach being erratic or not working at all.

radio flyer

Talk about pulling a corpse from the grave! Glad it helped you, and it's good to see that your not afraid of the search function. It can be a pain-- especially to old farts like me. Good luck with your new toy.

Lokdrok

That diagram saved my Jeep. I was without gauges for 7 months. You are a lifesaver!!

zanderander

So I just put a new cluster in and the sensors that go along with the upgrade from the dumby sensors and the speedo still doesn't work I have a new speed sensor the ground looks good and everything is plugged in??? What to do??? 1995 xj 200k

zanderander

Also the odometer doesn't work?? Any ideas

zanderander

Actually I do not have a new speed sensor just a new crankshaft position sensor

lewphelps

Did you check the ground connection with a VOM? The symptoms are CLASSIC for a broken ground wire. See the photo posted above by Radio Flyer. There are two wires that have slack and one that is taut. That's the one that breaks. It can be broken electrically and still not appear broken visually.

Try measuring resistance from the ground return at the speedo to the chassis. If it's anything more than zero resistance, the ground wire is broken.

If you don't have the electrical circuit diagram for this cluster, let me know and I will post it. You'll see that the three instruments you have that are dead all share a common ground wire, and nothing else is connected to that ground wire.

This is a straight-out case of factory design flaw. When they designed the harness, they made that ground wire just a fraction of an inch too short, which means it's taut when installed, which means vibration will break the wire sooner or later, right at the point where the wire exits the crimp connector.

Lew

zanderander

Hello Lew. Thank you I have not looked at that I even changed the speed sensor and nothing but got a question could it cause this:

Hey guys got a question. About a month or so ago my exhaust fell off from in front of the converter all the way back. It was super loud but drive it for a week or so cuz I had no choice. I drive an hour one way to work pretty much all highway. It started to sputter when on the gas no matter what speed. So I got a whole new exhaust system. It's a cheap one but it works took it to a mechanic an he drove it for 2 weeks said he couldn't find anything. Now after about two more weeks driving it with no problem it's doing it again but only at 70-80 mph and not as violent as before just a couple times. Any ideas.

I posted that last week and nothing yet?? Any ideas???

zanderander

Also I have checked the check engine light and it keeps giving me a different code I'll check again today MD let you know what code it is