electrical Q not on MJ, but XJ

[chunks6067]

so I'm working on a 95 xj, 4cylinder manual transmission, that has a problem.

I first diagnosed it as a bad alternator because it would die shortly after start with a good battery, or a good jump.

Then i took the alternator off got it tested, and it was good.

i also had the "good" battery tested and it was dead, warranty replaced it

then took it to the jeep, checked all the hookups and it worked ran for about 2 days, now i have a bright red battery idiot light on.

any advice i would greatly appreciate.

[jpdocdave]

the idiots at autozone or wherever it was tested don't know what they're doing. i've heard way more bad alternators called good by those idiots than they've ever gotten right.

 

if the light is on now, put a voltmeter on it, and test the output right at the alternator.

[Pete M]

I first diagnosed it as a bad alternator because it would die shortly after start with a good battery, or a good jump.

 

 

How soon is "shortly"? Fully charged battery?

[HOrnbrod]

Measure the charging voltage across the battery w. the engine running at about 1.5K RPM. Should read at least 13.3VDC.

[chunks6067]

I first diagnosed it as a bad alternator because it would die shortly after start with a good battery, or a good jump.

 

 

How soon is "shortly"? Fully charged battery?

 

 

about a mile up the road

 

 

I just havent got back to working on it because of school i think this weekend ill try a voltmeter to get a good reading