Codes U1110 and U1120, crank not start?

All fuses are good. The fuel pump is engaging. I have checked for corrosion on the relays and in the relay box. Neither show any corrosion.

Both of the codes you listed indicate a communication error between the powertrain control module and the ABS module. I'm struggling to determine how the two issues are related.

As far as the no-start, do me a favor. See if it starts for a couple of seconds using starting fluid. If it does and then stalls, we know there is a fuel-related issue. If there is no change, it is likely related to the ignition spark.

If there is no change, here is a link that explains how to check for an ignition spark:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

I understand the fuel pump can be heard, but it may not be producing enough pressure, the fuel injectors may not be getting a signal to inject fuel, or there simply is no spark to the plugs.

Try this and let me know what you find.

Joe

Thank you for the suggestions! The starting fluid had no effect. There seems to be an issue with getting spark. The video was helpful in testing that. Thank you.

Hi,

By chance, do you have a live data scan tool? If you do, can you check if there is an RPM signal when cranking the engine?

Let me know.

Joe

Well, I was able to temporarily fix this issue by replacing the crankshaft position sensor and throttle position sensor. I am now getting the same errors and feel like the sensors should last longer than 3 years. Is this a common issue with the Jeep Patriot?

So these codes will not make it not start. Can you clear the codes and try to start the engine to see if they come back.

U1110 - Lost Vehicle Speed Message

U1120 - Lost Wheel Distance Message

Also, will the engine run on starting fluid? Here is a good video to watch that can help you.

https://www.youtube.com/watch?v=lXLJbuAZ4CE&t

Pleas go back to use with what you find :)