Sig220

My 99 XJ has had a peculiar problem lately. The dash voltage gauge will out of the blue peg to the high side (19v) several times even in short drives at about 1800-2000 rpms. I don't let it go long before I reset it by shifting to neutral, turning the engine off and then restarting. But that only lasts a few minutes before its pegged again. So today I was going to take a short 20mile roundtrip and decided to bring my voltage meter with me. Sure enough I had not gone 2 miles and it pegged. This time I stopped on the side of the road grabbed the meter and popped the hood but by the time I got the probes on the battery it was showing normal range voltage. Did this again just a few minutes later. By the time I could stop, get the hood up and put the probes to the terminals it showed normal range voltage. So I stopped and bought some 2 conductor 18g wire and on the way home had the battery hooked directly to my meter in the cab. The voltage meter stayed normal this time until I was a block from my house then it pegged! To my surprise, however the meter was still showing normal range voltage. But the dash gauge was pegged and the "check dash gauges" light was on.

So at least I won't be burning any wires up if I still drive it, but it is annoying that the dash gauge is pegging triggering the check dash gauges light.

I thought I would ask here before I pull the parts cannon out to blast this problem! The only other clue is that the battery voltage with all things off will show in the low 12 volt range. May be a good time to replace some the factory battery cables along with the battery?

What are your thoughts?

IJM

Your battery cables are needing replacement. Been there, done that.

Sig220

That is where my parts cannon was aiming, along with the battery for good measure. I will reinspect/clean the grounds as well.

Thanks for your reply!

IJM

Yeah, do all of that. Your battery might be OK, though. When my battery cables were on their way out, I'd get all sorts of electrical craziness happening. Pegged voltage meter, random interior light flickering, totally dead when I went to restart it after making a quick stop, etc. I put on new battery cables and terminals 4 years ago and it's been completely fine ever since.

lawsoncl

Yeah, intermittent battery cables can do that, but you might also have issues starting if that were the case. Stick your meter on something inside like the cig lighter. Do the dash lights or interior light get really bright when this happens?

Sig220

All I have monitored so far is the voltage at the battery. I will in the next few days check it at other places. The dash lights and interior lights don't seem any brighter when the gauge is pegged. I also checked to see if the power windows worked faster, but they don't seem to.
The battery cables installed now seem kind of "flimsy" my leads off the battery are a lot heavier and stiffer as well.

What are the recommendations of cable size with a stock XJ? Also referrals to make the purchase. I will be doing a search on the net in a few moments.
Thanks Again to all who have responded.

Sig220

Started changing wires today and think I found the problem. The previous owner had installed battery clamps with "pig tails" attached to the clamps. they have big copper connectors with a allen screw connector in the end. You just cut back the insulation, stick the wire in the copper end and tighten it with the allen screw. Then slide a rubber/plastic over over the connectors. My first wire replacement was the ground to body and then I went with the hot to fuse box. When I pulled the hot out of the copper connector, I found where the insulation had not been removed and the allen screw was tightened on the wire where there was insulated. I replaced this wire with a new cable that has been soldered to both the copper eyelet to attach to the fuse box but also soldered the wire on the other end where I removed the insulation and then put it in the connector and tightened it down. Took about a 30 mile roundtrip and had no issues with the voltage meter pegging out! Over the next day or two, I will replace the rest of the wires as well just for good measure.