PSUmaninSC

"They're flying on instruments!" Except not...

Back story: 98 XJ for as long as I can remember the instruments (tach, fuel, speed) would sometimes go out and the airbag light would come on. Usually with a good bump or whack they'd pop back up. Recently it finally seems to have bit the dust, they have all gone out and won't come back on no matter how hard I whack.

When I first turn the key all the cluster lights still turn on, and its lit, but not even a wiggle on the gauges. Here's the kicker: The electric door locks won't throw, never had an issue with it before. They unlock function works, the lock does not. Very strange but given the timing I have to assume its related. Anyone have an idea?

RTorrez1

Iy sounds like you have 2 unrelated problems. The instrument cluster will have to come out and you will have to check all the connections and make sure that they are connected. Another common problem is the connections get corroded. You will have to clean them all really well and put some dialectic grease on them and that should hopefully take care of your gauge problem unless the cluster completely went out.

kennzz05

^^^^^x2

PSUmaninSC

I just noticed that the stereo is out too. Not getting any power at all. It all happened at the same time so I highly doubt its unrelated. I had read that the ground for those gauges are all the same one, is the ground for the power locks and the radio in the same place? If so can anyone tell me where it is?

PSUmaninSC

I just spent some time taking apart the dash to look in there at the connectors at the back of the cluster. It looks good actually, no oxidation or anything. I did some more research to see if I could get a diagram or something of the wiring and got nothing.

Most people when they have this issue have only the airbag/tach/speedo problem. I have total power loss to the cluster. All of my gauges are out, only the error lights and back light work. I'm convinced that the stereo going out and power locks are all connected. Are all of these on the same ground?

PSUmaninSC

I did some more recon, playing around with the two green plugs that plug into the gauge cluster and when I plugged in only the left one, the check lights came on but still no luck with gauges. When I plugged in just the right one, nothing. With both, lights, but no gauges.

I also checked my stereo wiring, and its all solid. No problems with the wiring. I am finding more and more that tells me its a problem with the ground/power to both of these. The fuses for both are fine. Can anyone tell me what the wiring diagram looks like for these, where they connect to the battery and where the ground is for the radio and instrument cluster?

CCKen

Which 'fuses' did you check. The ground is G108, on the underside of the dash near the headlamp switch. G108 is also the ground for the HVAC control. It's unlikely this ground connection is bad all of a sudden.

The IOD fuse powers these circuits. Pull the cover off the PDC and look at the mini fuse arrangement on the underside of the cover. The IOD fuse will be identified. Check this fuse.

PSUmaninSC

I pulled and checked the fuses for the Radio, Power Windows, and Instruments in the interior fuse box in the passenger footwell. None were blown. is this IOD fuse in the engine compartment fuse box? If so, will I be able to tell if it is blown just by looking at it? (I know a lot of those fuses are black box type, not easy to tell).

I didn't see the G108 when I did my dashboard disassemble rodeo, but if the IOD is fine I'll take another look. My next COA is to take apart the dash and use a voltometer to check and see which pins in the green connecter/radio are receiving power. Hopefully I can get this fixed soon, I don't care much about the instruments, but not having a radio blows.

CCKen

The IOD fuse is located in the Power Distribution Center (PDC). THe PDC is located in the engine bay next to the coolant overflow reservoir. It's a mini fuse, similar to the Junction Box fuses in the passenger footwell. Pull the cover off the PDC and look at the mini fuse arrangement on the underside of the cover. The IOD fuse will be identified. You can tell if it's blown after you remove it and eyeball the internal fuse element.

PSUmaninSC

Yep, I owe you Ken, because you saved me from a lot of extra grief. While I was contemplating a complete disassembly of the dash (again) and pulling out the ole voltage meter to check every individual pin and all of the grounds, I popped the hood and checked that fuse. Sure enough, it was blown. Replaced the fuse and VIOLA! All better.

I think what happened is when my gauges did the old blank out as they are apt to do and I gave it the good karate chop, the power surged and blew the fuse. If you hadn't said anything I wouldn't have even checked that fuse, I knew nothing about it.

CCKen

Glad to see it's fixed.

As a sidebar: There was a TSB from Chrysler concerning 1998 Jeep Cherokee instrument cluster problems. It involves the replacement of a connector at the cluster. You can see if the TSB was complied with by examining the wiring at the connector - it should be spliced in. Here's a TJ discussion about this sort of thing. http://www.jeepforum.com/forum/f9/98...solved-595954/

If the TSB wasn't complied with and you still need to apply shock therapy to the dash to get the instruments working, you may want to consider doing this TSB.