Feb 25, 2018 · U0101, while it points toward a loss of comm with the TCM, is commonly a main harness connection issue....which does all kinds of things down the line...like TCM, ABS and such. Pull and check the main harness/plugs. Also; Your signature has had adjustments. Please review the Forum Rules for what's acceptable there.

Feb 25, 2014 · Ive had the tuning for maybe about a month. Today when I started the truck, all the service traction control and other things were gone, the check engine light was still on, throwing a U0101 code and now also a P0880 code. There is now a line under the gear selector and I am also able to drive it now.

Nov 7, 2015 · The U0101 pointed to a bad TCM, and the new part fixed that. Now that the TCM can communicate properly, the bad solenoid code is able to be sent to the ECM. IIRC, there's at least one (if not more) good solenoid threads in the archive that should help you on this issue.

Apr 2, 2018 · Well, went out yesterday cranked my truck to leave and couldn't. Put truck in reverse to back out. After backing out put truck in drive with a very violent shift it went into drive. Noticed I had a cel and service stabilitrak warning. Cel was u0101 lost communication to tcm. Truck was also...

Sep 25, 2013 · For probably the last 2 weeks I have gotten U0101 and P0880 codes shortly after starting my truck and letting it warm up. It puts the truck in limp mode, illuminates the CIL and Traction Control light, and the DIC reads "service stabilitrack" "service traction control" and "service park assist."...

Jan 23, 2009 · U0101 Lost Comm with TCM Emmissions Warranty? no I don't think it would, but it should be covered. That is the Transmission Control Module losing connection/ communication, I would just check the plugs at the TCM to make sure that everything is plugged in correctly, maybe put some dielectric grease on the inside of the plug.

Aug 8, 2023 · I have the dreaded U0101 code. No other codes. The truck goes into limp mode after driving a few miles. Goes away after sitting for a while. Rinse and repeat. I’m on the waitlist for a new TCM. I pulled the trans connector and found fluid🧐 nothing dripping outside, only internal.

May 15, 2018 · Jump started the truck this morning and got the u0101 code immediately and "service brake system" on the dic. Watched some videos, ran the tests on the harness. No power to pins 10 and 70. Everything else checks out; power to 2 and 63 with ignition, continuity between 9 and 69. Why would I have no power to pins 10 and 70?

Jul 13, 2019 · U0101 indicates that communication with the TCM has been lost. If the LAN wires to the TCM have a problem it can set this code but that isn't all. Any module on the system that goes bad can ground out the LAN wires and kill communications across the network.

Mar 28, 2016 · Code:P0880 Modules:TCM Description:TCM Power Input Signal Code:U0121 Modules:Description:Lost Comm With Anti-Lock Brake Sys (ABS) Ctrl Mod Code:U0140 Modules:Description:Lost Comm With Body Ctrl Mod Code:U0101 Modules:ECM Description:Lost Communication With Transmission Control Module (TCM = = = ~