Where did my overdrive go?

I am the second owner of a 97 Cherokee 4.0 2wd. My overdrive works now and then. my check engine light is on. I had it scanned it throws 2 codes. p0700 and p0705. It has 147k and we already replaced the entire cooling system including flushing the engine and system thoroughly . Now it has been sitting for nearly 2yrs. just not sure what direction to go.

Those codes can indicate any of the following causes for the transmission problems:

Faulty wiring leading to the Transmission Control Module (TCM)
A faulty TCM
A faulty park/neutral switch
Faulty wiring leading to the park/neutral switch

I suggest that you take the vehicle to either a Jeep specialist or to an independent transmission shop for specific diagnosis & repair. DO NOT go to AAMCO, Lee Myles, Cottman, Mr. Transmission, or any other chain operation unless you want to be told that you need a new/overhauled transmission–whether you really do or not.

When it is in the shop, also have the transmission fluid & filter changed in order to forestall other trans problems.

Thank you .

For starters you can just find you range switch (P0705) on the transmission. It looks something like this: http://www.ebay.com/itm/like/321360954057?lpid=82
and should be on top of the transmission someplace. It’s probably operated by cable from the gear selector inside of the car. Inspect that whole wiring harness carefully for any sign of a problem. Unplug the thing and inspect the plug and the pins. Clean it up with some electronics cleaner. Eyeball the cable connection to check for anything amiss. Etc. If you don’t find any obvious problem, then your best bet is probably a shop and a scanner.

The P0700 is probably derivative of the P0705 as it is just a generic transmission control problem code.