WildCowboy71

I have a 1997 Jeep Cherokee that I have recently put a lift and 33x12.50's on and now sometimes when I drive it the check engine light will come on and stay on for a couple of days then go off for up to a week. I am curious what could be causing this. I am not sure if it is the speedo gear, the TCM, or the PCM that is causing it to come on. It seems like the Jeep shifts fine, although when the light is on it is harder to get it to down shift, or shift into overdrive. I am just wanting some input on what I should check or do to fix my BABY!! Thanks for all of your input and help as I am a newbie here and welcome the all of the input.

Jim

93gc40

Have the CEL codes read.. With around 1000 possible causes, it's kinda stupid to just guess.

WildCowboy71

The codes I get are basically saying that the TCM is not communicating with the TCM. One is a PO700 and the other is a PO1698

Thanks again for your help and input

jeeptech40

check connectors at pcm and at tcm also when changing to larger tires was the pinion factor spec changed can be done with scan tool at dealer most likely a wiring issue ohm check wires if connectors look good check bus wires from tcm to pcm also ohm them to power and ground to check for shorts