1998 Jeep Laredo Onboard computer problem?

Tiny
STACIARAE
  • MEMBER
  • 1998 JEEP GRAND CHEROKEE LAREDO
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 200,000 MILES
I have a jeep grand cherokee laredo, which has always had problems. ( Dome lights that wont turn off, alarm sounding numerous times a day) Now the battery wont stay charged. The battery and alternator are brand new. The jeep will boost first try and the battery stays fully charged after that, but if I go one day without driving, the battery drains completely. Any idea whats going on here?
Thursday, April 3rd, 2008 AT 1:18 PM

1 Reply

Tiny
MERLIN2021
  • MECHANIC
  • 17,250 POSTS
Get an analog voltmeter remove the negative battery cable, attach the Black lead to the battery post, Red lead to cable end, then pull fuses one at a time, make sure there are no accessories or lights in the on position, Key off! Close the door after each fuse and check meter, when you pull the fuse for the bad curcuit, the meter will drop to 1 volt or so. Check all fuses, even under the hood. If meter does not drop, remove the battery connection from the alternator, if it drops now, the diodes are bad in the alternator. Put the fuse back in were it goes as you go so you don't forget which fuse goes were!
You have what is known as a parasitic drain!
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Thursday, April 3rd, 2008 AT 1:22 PM

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