C1340/U0126 codes

Hello fellow Tundra folks,
Chasing a frustrating issue on my 2013 CrewMax. Codes C1340 (Center Differential Lock Circuit) and U0126 (Lost Communication With Steering Angle Sensor Module) coming up. I was in 2WD when the C1340 first appeared. Most forums say that the C1340 will prevent shift to 4WD, but I do not have that issue, and can shift in/out of 4WD. 4WD lights up as expected, no flashing.

One forum may have linked aspurious U0126 to a battery going dead, which did happen to me.

Finally had the truck at our local Toyota dealer for diagnosis. Tech got frustrated as unable to replicate, and all Toyota debugging steps came up as good. So, dealer ran a Zero Point Calibration at no-cost (that was nice!) and sent me on my way to monitor. Nothing in the week since.

Any inputs or experience from the community?
Thanks!

 

If for example during cranking, the battery voltage drops off, and communication on the CAN bus between the countless computers falters, erroneous codes get sent / stored as it's pinging a module for data and gets garbage in return due to system under voltage, many codes can come up that aren't real issues.

With a new battery I bet the steering angle sensor never comes back.

As for the real xfer case, if the Yoda tech can't duplicate or shed light on it, and it didn't happen during battery incident, I've got nothing...

If it did happen with battery issue and it's gone now, it may not have been a real issue.

That's why it's good to have a means to read it yourself and look at the Freeze Frame data and see the system voltage.