98 jeep cherokee alternator works sometimes

[lunchbox07]

I have a Cherokee Sport 98'. I have replaced battery, had alternator tested twice and ran good both times. I've ran the voltmeter test when working and not working. It does not charge when not working. The gauge will show 12.5 volts upon starting then after 5 minutes of driving will go to 9 volts and check gauges light comes on but lights do not dim at all. When i get home to check it i shut it off for no more than 5 minutes and start it back up and its working again til i take it to work the next day. Any suggestions???

 

[lunchbox07]

Need some help on this please, we have been working on it for two weeks and are completely stumped on why it will work then not work then work again????? Need some suggestions

 

[volaredon]

internal short replace it!

 

[lunchbox07]

In the alternator or elsewhere? Jw I read another post on here and they talked about a battery temp sensor, thats the only thing we havent checked. Besides digging thru wires. Would that have any thing to do with it?

 

[Bounty__Hunter]

Have you tried replacing the alternator?

 

[Jester32]

Are the connections tight on the alternator.