I was delivering newspapers this morning for about 2 hours and was sitting and idling, smoking a cigarette when I got a chime alert. I looked at the dash and it said "check gauges", all the gauge needles were down, and the Security Key lamp was lit, then everything came back on line just about instantly but the key light was still lit. The engine never skipped a beat or faltered. Now I'm worried! I continued to deliver my papers for another 3 hours with everything acting normal, watching the gauges like a hawk, hoping to get the job done. I got home in my driveway and shut it off.

I pulled the key out, waited about 1 minute, put the key back in, and it fired back up like nothing had happened! Security key light went out. WTF? I'll try it again after I chill out awhile, but it has me worried. I haven't a clue as to what caused the glitch or if next time to won't start.

Anybody else had this happen? 2000 WJ, 4.0, 235K miles.

 

The notorious WJ electrical gremlins. It's what I worry about driving a WJ. I lack enough understanding of its systems to hazard a guess.

 

Sounds like a low voltage condition existed, maybe from a poor intermittent connection, that doesn't currently exist.

What about first removing the battery negative terminal, then removing / inspecting / cleaning / reassembling every battery and ground connection?

That won't hurt and possibly could help this problem.

 

Ya know Wingless, I think you're on to something. I've noticed the volts wandering a little the past couple of days, drifting between about 13.5 and 14.25, not all the time, just once in a while. Time to do some electrical maintenance! I was wondering about the alternator brushes.

 

I have read alot of posts about this same thing. It's not just Grands its all Cherokees from what I had found after mine started acting up.

Could be the plugs that go to the back of the cluster. Mine is random all the gauges will drop to zero and the airbag light comes on. then just back up on their own or sometimes i hit the dash and they come back on lol i havent gotten around to pullng the cluster yet

 

Okay...Yeah. About a year and a half ago I came out to start it and the battery was flat. I stuck the charger on it for a couple of hours and when I went to start it, the tach and speedo went all the way up and back down again, then up, the engine started but the needles stayed all the way up. I drove it to Battery World to have the battery checked and I had one cell shorted. I bought a new battery and that took care of the problem. Strange things happen when the voltage isn't right.

This is exactly what I needed. A couple of clear heads not involved with my anxiety! All those 18 year old electrical connectors that may be getting dirty and to make matters worse, we ripped the dash out last year to replace the heater core!

About an hour ago, I started it and drove it around the block with zero problems.

 

That is really, really strange...


That people still read paper newspapers. Sorry, couldn't resist.

 

 

As one of my elderly customers said "Ever try sitting on the toilet with a laptop?" "You can't soak up dog **** with a laptop either!" Actually that's about all the Post Standard is good for! LOL! I'm making $240/week working about 12 hours total but burning my own gas, tires, and brakes. Social Security pays the bills, the Post buys beer and groceries.

 

I had the mysterious Check Gauges chime once, couldn't figure it out, ...it was the alternator. It should say Check Alternator ...Your voltage is Low gauge. Pretty neat that they can monitor that and set a chime. One thing that will make the alternator flaky, is if you have a coolant leaking on the alt. or if you drive through a massive puddle. Mine was just a bad alternator.

 

I was thinking more like worn brushes, especially with 235K on the original. At least I think it's original. It's bright and shiny, but I don't remember changing it. It's mounted high on the engine above the tensioner.

 

Quite rare if it's the OE with that high of miles.
But surely worn brushes will do it. I rebuilt one myself, actually 4 times, recently, just to see what's up with them. The one I pulled apart the brushes were worn, yes, but the copper rings they ride on seem to wear just as much, and when you get through them its lights out, literally. And as far as replacing the bearings, there is another picnic!!. Replaced both of them which mind you is not easy, and the rotor still would hang on the stator. Belt squealing like a banshee on startup. Oh! Such fun to pull it off and do over. My advice ..bite the bullet for a new one, with the limited lifetime warranty LOL.

 

I used to rebuild GM alternators in the 70s. I never had a rotor/stator problem because the stator and the 2 case halves indexed in tabs. The brushes were soft so the slip rings didn't wear much and both bearings were like $5 combined. The most expensive parts were the rectifier and diode trio. Sometimes I'd find melted stator windings.

Thanks for the headsup on the Denso alt. I'll have to dig thru my records an see if I have a receipt for an alternator, but if I do, it's got to be almost 100K ago. I DO remember replacing one on my 97 ZJ, doing the wires from underneath!

Okay, Found it! 7/25/17. How quickly we forget! I did the front brake pads at the same time. It must be senility creeping in.

 

have done a few GM's they are straight forward. These densos...man I did the xj like 3 times in and out, and it still chirps on start up.
You found the receipt? so it still under warranty

 

You were choking the poor thing, quit smoking...