2010 liberty abs and speedo issue

[Skooterking5]

Hey there, my mother in law has a 2010 jeep liberty 4x4 with 117k miles on it. She asked me to take a look at it. With it running it has the following lights:
ABS
ESP
BAS
Serv 4wd
Brake
And check engine
Speedo is also dead, no vehicle speed reported on live data from odbII.

Upon reading the DTC codes I come up with:
U0121
U1120
U1110

Not sure what to check, I have disconnected all modules and reseated them under the hood, went ahead and replaced input and output speed sensors on the transmission. Wiring and sensors to all 4 wheel speed sensors seem fine. Not sure what to look at next. She says when she drives it usually the lights stay on and speedo does not work on short trips, however, on longer trips (20-30 mins) she says the speedo will come alive and all lights will turn off other than check engine. I do not have a high tech scan tool, I have an BlueDriver just FYI. Any ideas?

 

[Kawika]

My 2006 CRD did the same thing a couple weeks ago.
The battery was reading 10.6 volts so I replaced it.
Some change in the lights on the dash.
The alternator test showed a 11.5 voltage output so with 160,000 miles it was time to change the alternator and then cleared the codes and no prob since.
I did learn from this that no1 glowplug was not working good.
Changed that and it really runs much better with new plug.
Bottom line is your alternator can kill a good battery by not producing enough voltage to keep all those systems with lights on to function correctly.

You can check your alternator diode pack by switching you volt meter to A/C instead of D/C ,and when running, check for A/C voltage leaking from pack by putting tester on red and black to see A/C leaking past that pack.
If it reads anything much on A/C side its just t he diode pack which is an easier fix.
Good luck.

 

[Glenn Buskirk]

My daughter's '06 KJ 3.7L has similar symptoms (ABS/ESC/BAS lights, no speedo), but it has rodent damage to some wires, near the firewall under the brake master cylinder. Similar codes too, I think an U1120 and a P0501. I just bought a new harness (New, old stock) off Ebay for 2006/2007 KJ's, and I hope we can replace it ourselves or find a shop to do it for us.

 

[Kawika]

Good luck I imagine that the gasser has alot of the same logic.

 

[Skooterking5]

Thanks for the replies, she’s taking it to jeep to get looked at. She took it to another shop and they told her probably the abs module is shot, so we will see what jeep says and I’ll let you all know.