I have had my 99 xj 4.0 for about a month now. Using a code reader it shows codes p1698 and p1694. I know they something like the engine and tranny computers are not reading each other. The thing is that the Jeep runs just fine and shifts fine too. I also have no check engine light on. I checked and yes the light bulb does work on the dash. Is this something I should be worried about?

 

Search google. Usually gives all information.

 

Yes I did google them and I know what they mean. Everything that I have read is that these codex don't allow the Jeep to start or run. They're check engine light is on and sometimes its the cps. The thing with my xj is that it starts fine and it shifts fine too. I also have no check engine light on either. I just want to find out why those codes come up if its running fine

 

Clear the codes and keep trucking. The code(s) may come back at some point with a CEL, and/or you will have additional problems like no instruments.

P1694 doesn't always have a CEL. Here's the info for P1694 W/O CEL:

P1694 Fault In Companion Module - No CCD/J1850 messages received from the powertrain control module-Aisin transmission

P1698 has two configurations, neither of may have a CEL.

P1698 No CCD/J1850 Message From TCM - No CCD/J1850 messages received from the electronic transmission control module (EATX) or the Aisin transmission controller.

P1698 No CCD Messages received from PCM - Bus communication failure to PCM. A "

Companion DTC" was set in both the ECM and PCM.