In th emiddle of a long highway drive last night, my Check Gages light came on and the battery gage went to the minimum of 9.

Driving and lights not effected at all. No stalling or hesitation when I arrived home and was driving at street speed.

Started without a fuss this morning with battery gage back at 14.
I drove a few miles. On the return drive this morning the bat gage went back to 9.

novice would apprectiate a starting point in understanding this.

Thansks
-Novice in NY

 

Get out the VOM and CHECK your voltages. The battery should read less than 13V with the engine off. With the engine running it should read close to 14V as its being charged by the alternator.

Make sure you battery cable and post connection is not loose or corroded. You can clean the corrosion off and apply dielectric grease.

I definitely would want to check the battery with the engine running when your gauge shows 9V just to see if its just a flaky gauge, or bad connection to the gauge.

 

Look for a place that will load test your battery and also test the altenator. Some places will do it for free and tell us the results.

 

Same exact problem with my 98. Was pounding around out in the sagebrush and lava beds in it, and the "check gauges" light came on, with the volts dropped to 9. It ran for about a week on the battery, then this morning, I started it up, turned the lights and heater blower on, and made it about a half block before I turned around and coaxed it back to the in law's driveway. Dead as hell now. Prior to this, the whole gauge panel would go down, and a good thump to the dash would bring them back.
When the sun finally came up, I discovered that the battery cables were loose, that is, the cable ends had been replaced with the cheapie clamp-together replacement ends, and the caps were loose and corroded. Got the battery on the charger, but I'm not hopeful. Research says that the voltage regulator is in the ECM, or PCM, whatever it is on the left front inner fender well. Replacing that, the alternator, cables, and most likely the battery and belt is approximately a $500.00 bill.
It may be cheaper to just get the small block Chev conversion setup and go that way, but I sure like 27 mpg on the highway out of this rig.......

 

First thing to verify is all connections and your battery. Target charging for a healthy system is around 13.5 to 14.0 volts.

Confirm what the gauge on the dash is reading with a voltmeter. Confirmation is important and only takes 30 seconds.

Grounds can also be an issue. Below is more on that.

If this continues after above, your alternator is most likely going bad.
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Grounds can be the root cause of many electrical gremlins. Refreshing grounds is NEVER a bad idea!

You can't just check or look at these grounds. You must remove, scrape, clean until shiny the cable/wire ends and whatever they bolt to. The one on the back corner of the head, and where it attaches to the firewall. Scrape the paint from the firewall. Best to replace that woven cable with a #4 or #2 gauge cable. You can attach the one end to the intake manifold if you would like.

Next go over to the engine dipstick tube stud. Remove the nut and clean the wire ends and scrape the block until shiny at the stud. Reattach tightly.

If you are so inclined, add at least a #6 cable from the negative terminal of your battery to one of the bolts on your radiator support. Scrape the paint off first.

 

Checked that the dash mounted gauge was showing what was actually happening in the engine compartment, and it was, except that the lower-end range of the stock gauge didn't go low enough to actually display how low the batt/charging system actually was at.
Pulled the alternator, swapped it out, and cleaned/protected every connection that I could get to. Works great, and I sure hope that I don't have to do that job again! These days, just getting down to crawl under the front of the Cherokee ain't bad, but 40 years of ladders and steel floors in missile silos ain't been good to my feet/ankles/knees/back, and getting up more than a couple of times have left me reaching for the old stash of pain meds.
Couple of days later, with about 200 miles of local driving (within easy reach of assistance, that is) has me confident that the fix (new alternator, belt, and now, the onboard tools to do the job) is good, and everything's running as it should.
By the way, the original alternator had 182K on it when it went south. In the near future, I'll be looking to replace the power steering pump, water pump, and tension pulleys with fresh pieces with good bearings. No noise at the moment, but it seems that with my luck, when one thing goes in the dumper, the fix shows a weak spot somewhere else!