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chickenbot
November 17th, 2017, 13:04
How do I fix this?

http://i67.tinypic.com/smczm8.jpg

I've ran a volt meter at the battery and it shows 14.0V solid

chickenbot
November 17th, 2017, 13:16
93 4.0l ax15 np231

lawagoneer
November 17th, 2017, 17:29
Need a little more information, what alternator, battery and cables. Have you checked the voltage with a good multimeter or know accurate gauge? The dash gauges leave a lot to be desired in the accuracy department but usually read lower than actual.

lawsoncl
November 17th, 2017, 17:33
Little tiny stick on numbers and recalibrate the scale. :}

90xj06
November 19th, 2017, 17:12
is this jeep new to you or did this just happen? if its new to you it maybe that someone popped the needle off and put it on wrong.

chickenbot
November 20th, 2017, 07:38
Need a little more information, what alternator, battery and cables. Have you checked the voltage with a good multimeter or know accurate gauge? The dash gauges leave a lot to be desired in the accuracy department but usually read lower than actual.

stock alternator
58 battery from walmart
stock cables

is this jeep new to you or did this just happen? if its new to you it maybe that someone popped the needle off and put it on wrong.

new to me a year ago and has always showed the same. the cluster looks like nobody has ever been in there before

chickenbot
November 20th, 2017, 08:42
I have seen it go as high as 19V

techno1154
November 20th, 2017, 09:26
I have seen it go as high as 19V

I do not see a post where you tested the voltage at the battery to verify the reading is accurate or not accurate. If you do not have a volt meter, drive to one of those discount parts store i.e. Oriley's, Auto Zone etc. They will be happy to test it for you.

You replaced a battery recently, Did it die because of old age or because it was overcharged? At 19 volts, I do not imagine a battery will live many hours.

On the 1993 XJ's, the charge controller is built into the PCM (computer). Is this still true of your XJ or did some one installed an external regulator?

Finally, if everything on your XJ is actually OEM then you need to have the wires at the back of the alternator tested to ascertain they are not shorted to ground. Of the two small wires bolted to the back of the alternator, one is dark green and orange (dg/or) and the other dark green(dg) tied together in a block. They tasked with turning the alternator on and off. The dg/or should have 12 volts positive continuously when the engine is running. This seem to be true because alternator output is verified via the dash gage. The other dg is a pulsed ground controlled by the PCM. This is what regulates the charging voltage. If this wire is shorted to ground, the alternator will charge flat out at all times which could go as high as the 19 volts you are seeing. The only way to test this dg wire is to remove the block from the alternator and test it with an OHM meter.

First things first, verify the voltage is actually 19 volts by testing at the battery with the engine running. If this as true the next step will be trouble shooting to isolate and remedy the cause.

lawagoneer
November 20th, 2017, 13:51
Yes first step is testing with a multimeter or accurate gauge. I asked about the alternator as some high output ones are set to 14.6-16 volts. Heavy-duty cables and solid grounds will let the gauge actually see better voltage, the factory dash volunteers are not very accurate even when new.

If it is truly 19 volts then the regulator is possibly your problem.

Johnnie Walker
November 20th, 2017, 15:58
Op first post states 14V @ batt

chickenbot
November 20th, 2017, 16:06
When I ran a volt meter over the battery terminals I got 14V solid but the gauge, as it shows in the picture, I'm guessing 16.5V.

I don't know how old the battery was when I bought the Jeep. The guy I bought it from bought it from an impound just barely wrecked(needed a new hood and front nose).

chickenbot
November 22nd, 2017, 09:38
This is what I'm talking about when the gauge hits 19V. By the time I got somewhere I could put a voltmeter on the battery it was already back to the 16.5V on the gauge.

http://i68.tinypic.com/6j2fyp.jpg

techno1154
November 22nd, 2017, 12:21
Do a different test:

After the engine have been running for awhile, and before shutting it down, have someone hold the engine to about 2,000 RPM. Test the voltage at the battery terminal and compere the reading at the battery to that of the dash gage. This will give an idea as to the accuracy of the gage and how to proceed. I would like to say the dash gage is wrong but it need to be verified against another gage or volt meter.

14 to 14.3 at the battery is perfect with the engine running. 15+,....not so good.

chickenbot
December 5th, 2017, 16:15
So I was able to get a meter on it today and it was showing 14.6-14.7V reving to 2000RPMs all while the dash gauge was showing 18.5-19V

ehall
December 5th, 2017, 18:25
Might need a new cluster