Jeep Grand Cherokee Wk Shift Issue

[Edge76]

Hi all. Wonder if anyone can help I know its not a proper Jeep lol. But my 2008 Grand Cherokee has a fault where I will be driving and the service brake assist warning comes up on dash as this happens the P R N D on the dash are all lit up as if you have selected all the gears. There is a lack of go and it doesnt want to change up gears then the lights will flicker and go back to drive and all will well again! This happen once a month ago after charging a flat battery and has not done it since until yesterday when it did it 3 times on a 10 mile journey. Any Advise grateful.

[JPNinPA]

With any weird issues start with checking the battery. Have it load tested along with the alternator. Clean the posts and connectors to bright polish. Then follow each of the ground connections from the battery and clean those connection points to a shine snd reassemble. Then the same for power. While following the lines inspect fir corrosion or breaks. Replace if corrosion or damaged wires are found.

Do you have any check engine codes?

The only other item is to wiggle the shifter maybe put it in N then back. Possibly she select switch or connection is bad.

But being this first happened with a dead battery the battery or connections are most likely.

Cold weather takes out batteries.


If it continues take to a dealer to have the pcm or trans module reflashed.

Never look down on anyone unless you are helping them up - Jesse Jackson

[Edge76]

Thanks very much will check this today. I also have a spare gear stick unit complete. That I bought for the 4wd switch so could swap it out if battery checks out ok. Thanks again