Question about 1998 Jeep Wrangler

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Voltage irregularity I have a 2000 wrangler 4L. Yesterday my volt gauge would peg all the way past 19 and then the whole cluster would intermittently go out (every gauge to zero) and then come back on again with the volt meter again pegged. I changed the alternator about a year ago. I hooked a meter up to the alternator output and it is reading about 18. Someone told me the voltage regulator is in the ECM however. Any ideas?

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  • joez11 Jan 28, 2009

    I just got a new alternator and a sticker right on it along with a tech sheet says "alternator externally regulated" . Now I am confused. The old one was tested and failed the DC volt output test. Help..



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You posted car as 1998 and 2000. so you will get wrong answers.

yah think?

18v is illegal, bad meter or bad reg. (or reg inputs wrong)

where the reg is located, we need hard facts.

engine size. 4l>

year car. (nebula's post....???????"??)

ill anwser for 2000, ok?

wrangler 2000,. aka TJ jeep, 4.0L ,one of 5 million engines.

the EVR is in the PCM read page 8c-2 here

so that covers your car, read the charging chapter, and the wiring pages.. and next time dont post to 1998,,, ok.?/

my guess, is the main fuse box is dropping man power to 0volts

so are the battery lugs clean and tight on ALL 4 ENDS?

that be first.

and is and easy problem , total loss of elect power is.

and a voltmeter finds this easy if you can make it fail at will.

super easy find.

called voltage drop testing 101./

Posted on Jun 08, 2015

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Well that's ABSOLUTELY NOT TRUE, the voltage regulator is in the ALTERNATOR. This vehicle needs an alternator and that should take care of this problem. Good luck and thanks for using FIX YA

Posted on Jan 27, 2009

  • dan israel
    dan israel Jun 07, 2015

    I know for a fact 2000 Grand Cherokee 2000 4L is controlled by ECM



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