jeep grand cherokee almost cranks doesnt turn over

I would assume that you mean the engine starter and battery ( Headlights are bright ) are good and the engine turns when you have the key in the start position but the car does not start. Common problem with these is the crankshaft position sensor - Sits in the rear of the engine and attached to the bellhousing somewhere. You didnt say weather it was a 6 or an 8 so here is what the 6 looks like

I would go with the the starter if the engine is not cranking, if you were low on oil, if you were low on oil, the engine may have gotten jammed, try getting a torque wrench and crank the engine manually, then try to start it. if that doesnt work, try figureing out where the starter is, hit it a couple times with a hammer and if the engine starts after that, then you need a new starters as it will get stuck again

i dont want to state the obvious, but have you tried replacing the battery/alternator? those may be easier than jumping right to a bad starter or a seized engine. it would have made some pretty loud and earsplitting noises before lockup anyway. i had a 99 gmc envoy that the alternator went bad on, it stalled while driving down the road. then would not restart until i put a new battery and replaced the alternator

sometimes its just the battery cables. I had this problem and it was very intermitten. I had a bad connection. My wires were corroded and i replaced the terminal for the ground. check there before spending too much money

diagnostic basics, does the engine turn by hand ? if not, does the engine turn by hand when you remove the serpentine belt ? if not, does the starter retract when you turn the engine some in both directions ? Lets get those tried and answered to see what the condition of the engine, the starter, and the driven accessories are. I had one of each in the last 20 years. one of them had a power steering pump issue not letting it turn, another had a starter staying engaged, and another was through bathing itself in 10w30.

The crank sensor issue is for a 6 that cranks and cranks but wont start. there is one service bulletin for sensors, and another for sensor connector pins loose fitting, there is an improved update part, but still, as difficult as it is to get to, you want to perform the pinpoint test properly before throwing parts at it, and use only CROWN automotive replacement parts.

inspect your battery's water levels, clean your connections, load test your battery, and verify ohms to ground for your battery's ground cable. on the 6 they attach it to a painted coil bracket and it can have as much as 30 ohms resistance, that means your whole ground is a backfeed for all the years it has been trying to crank, start, and run. AMAZING.

it is no wonder they eat computers .

My girlfriend has a jeep Cherokee and it will not torn over we change the Battle and the relay and it is starle not starting so it has to be the starter or wharl that gos to the starter a lot of things to do for this make

Start with basic electrical, obvious issues may exist, then go to the service bulletins and recalls that apply to yours, some were rewired this set of circuits, fuse links and around the power distribution center. The cables have a few possible areas to fail, the ground for the engine, body, computer and battery must all be within .5 ohm of one another. I f you need help with those basics you can get te recalls and bulletins to read and basic auto electric testing books at the library or have your components checked individually by a tech, then clean and correct every corroded or painted connection. They were a real pile, but you can fix them yourself.