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'98 Jeep Grand Cherokee - Power Issues

I have a 1998 Jeep Grand Cherokee. Earlier this year, I encountered some issues with the interior dome light flickering on and off while driving as well as the alarm going off in the middle of the night. This resulted in draining the battery on a regular basis. I took it to a local auto shop that specializes in Jeeps. Initially they thought it was a door latch issue and replaced the door lock actuator to the tune of $300. After I brought it home I did not have the problems with the alarm or dome light but the battery was still being drained (I could not leave the car parked for more than a day without the battery being dead). The mechanic replaced the battery and the body control module for another $500. Still the battery was being drained on a consistent basis. Since I have a 1 year warranty on the work I have taken it back numerous times (over 5 times) to the mechanic and he has reset the body control module 2X as well as run tests to see if there is a surge or inordinate draw on the power supply. He can?t find anything that explains this. Last time we picked up the Jeep at the shop, the mechanic told my husband that it might be the alternator. I went out 2 days after having the car back, unlocked the doors with the key fob, climbed in, tried to start the car and the engine turned over twice and then complete silence (e.g. no power). Any thoughts on what it could be and if it is worth sinking any more money into this albatross of a car? And if so how much I should expect a new alternator to run? Thanks all!

I don’t know why the tech can’t find the battery drain problem. If more than 80 milliamps of current is being drawn fron the battery while the car is parked then a seach needs to be done to find out what is drawing the extra current. Really, 30 milliamps is more a typical figure for a normal draw.

The alternator should be checked doing a load test to see how it is working. A rebuilt one may cost around 200 dollars, as a guess.

Why in the world would they replace a door lock actuator if they thought the door wasn’t latching all the way?

Sounds like you need a new mechanic. There are a few low cost items that can cause this problem. Have the door switches (not latches) adjusted. They are mounted in the lower body pillar below the striker. If they are not closing properly when the door is closed, they can be the problem. These switches are what signal the body control computer to turn on the dome lights and also work with the alarm system.

At least that is where I would start since they are not that expensive to replace.

I had a ford ranger that had a penny in the cigarette lighter that did this, might check that