Antilock Braking System (ABS) issue

[Phil2020]

I know that there are some amazing and experienced people on here for KJ Jeep issues so I am calling all to get help sorting this issue out...

I have a Antilock Braking System (ABS) issue that keeps coming up on my "Autel" scanner for my 2002 Jeep Liberty Ltd 3.7ltr.

It is the U303B-00 issue.
I went to the dealer and asked for a scan, $50. And they came up with nothing.
The dealer didn't know what the issue is or what the code means either.
I have tried other scanners and some come up with this code too.
I will put up a photo to show how it comes up on the scanner below.
If you can help Muchas gracias that's Scottish for Thank you very much for all your help

Many thanks in advance!

 

[Gyro]

https://dot.report/dtc/U303B

This is all I could find.
Good Luck

Gyro

 

[Country2003KJ]

I bought my 2003 and it always had an ABS light pop up once it awhile and it would go away after a drive or it would come one while driving and then would go away during the drive. In addition when I would back out of the garage I would get squeeks and metal grinding noise. Peridoically I would take the wheels off and do a quick look and the rotors were fine and no low brake pads. I did get a "right front" ABS error message. I thought about taking it off and looking at it, but decided that if I was going to do that I would just replace all the rotors/brake pads and start over with new.

Once I replaced the 23 year old rotors the ABS light never came back again. In my case I got some weird readings with my scanner but in the end I just needed to replace old rotors that were giving the ABS sensor an erratic reading. Along with new pads the scrapping and squealing sounds went away.

In your case, how old are your brake components? Have you cleaned the brakes? Is it possible that you may need to replace your hardware?

 

[u2slow]

Possibly a bad wheel/bearing sensor?

ABS was optional on the Liberty. Maybe take the option to ignore/defeat it? Been very content with our non-ABS KJ - just sayin.

 

[Phil2020]

First: A BIG THANK-YOU to GYRO for finding that code. I checked with the older higher ups at Chrysler and they agreed that there is nothing to worry about. It's called a Ghost code.
It's there to keep the trim and check that the ECU is working correctly. Weird I know but it's a Chrysler!

 

[Phil2020]

Second: Another BIG thank-you to

Country2003KJ​

I did change the front brakes and the rotors with Bosch coated rotors and Bosch ceramic pads.
The calipers at the time were okay didn't seem damaged or worn etc, and the cables around them were okay too.
The calipers were tested and checked worked fine.
Although I don't have a engine light on, it was a weird code U303B-00 that was throwing me.
With getting no other codes other than that U303B-00.
What was really weird was I getting a code for my ABS (air bag system), on my Autel scanner, but no engine light came on.
Managed to get a brand new module and left/right sensors, so out with the old and in with the new, and now the Autel reads no codes.
But I thought if you have an Air Bag problem it shows on the cluster as an engine light problem, am I wrong?

ps: By the way Country2003KJ, the wife thinks my hardware works pretty well

 

[Phil2020]

@u2slow
The module is there and has been pressure tested and checked out working fine.
It kicks in sometimes, but it's haunted and only works a night