Chrysler Repair: Jeep Ground-out Issue, chrysler corp, dash lights

Question
My 1994 Cherokee 4.0 L Auto has not wanted to start lately.  The battery, alternator, and starter are all fine.  Sometimes I will turn the key to the ON position and all the dash lights illuminate normally, then the next time nothing will.  Or vice versa.  My theory is something is grounding out the battery and draining it- whether it be a bad ignition switch, etc.  Both cables are brand new.  I can jump the car, drive it for hours, cut it off, and immediately it will not start again.  I am really confused here.

Answer
Hi Justin,
I don't have any wiring diagrams for Jeeps but if they are typical of Chrysler Corp. engineering then my thoughts are that it is not something grounding out the battery and draining it because that would not happen immediately without a large arc or something smoking. Rather I would suspect the ignition switch has a poor contact internally. You could try spraying some electrical contact cleaner into the interior of the switch.
The other possibility is that one of the ground contacts of the cable on the - post of the battery is loose or not making good contact. So trace along that cable to the attachment to the chassis as well as to the motor and make sure those are clean and tight.
When this happens again, check to see if the headlights work, for example. Then if they do you would know that it is in the ignition switch. If not then the battery cabling is loose somewhere.
I hope this is helpful to you.
Roland