Ive had a thread going in the OEM section for a couple days with a lot of views, but not too much help. Thinking its kinda run its course and might need to be in advanced since its help with direct codes that I cant find ANY info on. Ive been searching the web all day, literally.

Anyway, if you want to check the thread, its here:
https://www.cherokeeforum.com/f2/che...e-light-96720/

But my basic problem is, after changing my heater core and putting everything back together the CEL came on and its throwing a 1494 and 1694. No, I did unplug some of those vacuum lines, so Im wondering if that might be my issue. But on the 1694, its a transmission issue and I can, for the life of me, guess what the problem is.

A friend who owns the local garage checked it this morning and said it didnt make any sense so he cleared them. 5 miles later they came back on. I dont really dare to go anyplace, and its my only vehicle, so if I have a trany problem I need to figure it out. Thanks in advance!!!!!

 

Wow, nobody?

 

Code: P1494 Leak detection pump switch or mechanical fault.


If you were moving around some vacume lines you may want to recheck and make sure they are all still connected. Esp the vacume line on the side of the intake manifold. That is the main supply to the LDP system.
I couldn't find anything on the P1694 code

 

PCM and TCM not talking. There is a plug to the tcm under the dash by the accelerator pedal. Make sure it's not loose. When you re-assembled the dash following the core replacement, did you tighten up everything? Could be a so-so ground.

Let me know

 

Appreciate it guys.

The 1494, yeah, Ive checked over all the vacuum lines and everything seems to be in order. Cant find anything disconnected or rotten.

The 1694 I know what it is, but for the life of me I cant figure out how or why, especially since I drove like 5 miles before the light came on. Maybe a ground issue? Everything went back together as it came apart, so Im just really bummed out that Im throwing codes now. I was pretty happy about changing the heater core, you know, BIG JOB, so now that Im having issues really sucks. ESPECIALLY since its our only daily driver.

Hoping I dont have to pull the dash BACK apart.

 

Did you reconnect the tcm ??