# U0121 on the 2016 GMC Yukon

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

## Bulletins for this model year that name U0121

- [10162127](https://open.wenmarpro.com/bulletins/10162127), 2019-07-08: This Preliminary Information communication provides information to the technician about vehicle with Service ABS and/or Traction control lights/message on, Service Power Steering System, Service Suspension System, and or Loss of communication with EBCM, SWPS, PSCM, and/or SCM. Technician may find Diagnostic Trouble Codes U0077, U0121, U0126, U0131, U0139, U0401, U0415, and/or U0428. Technician should remove the driver and passenger sill plate to gain access to the wire harness. If any open, damaged, or corroded wires should be repaired.
- [10143433](https://open.wenmarpro.com/bulletins/10143433), 2018-08-06: This Preliminary Information communication provides information to the technician about vehicle with Service ABS and/or Traction control lights/message on, Service Power Steering System, Service Suspension System, and or Loss of communication with EBCM, SWPS, PSCM, and/or SCM. Technician may find Diagnostic Trouble Codes U0077, U0121, U0126, U0131, U0139, U0401, U0415, and/or U0428. Technician should remove the driver and passenger sill plate to gain access to the wire harness. If any open, damaged, or corroded wires should be repaired.
- [10125125](https://open.wenmarpro.com/bulletins/10125125), 2017-12-14: This Preliminary information communicates a false setting of DTCU0121 in the FVCM due to a FVCM software anomaly. Code U0121 will set and be moved to history in the FVCM with each ignition cycle.
- [10115119](https://open.wenmarpro.com/bulletins/10115119), 2017-08-15: This Preliminary Information communication provides information to the technician for a reduced power message, steering assist, engine stall or the instrument panel, radio, and or Heater\-Vent\-Air Conditioning go blank with multiple diagnostic trouble codes. If any of the following diagnostic trouble codes U0073, U0078, U0029, U0028, U0415, U0140, U0126, U0121, U0101, U0100, C0544, U1510, U0073, B127B, B2605, B3600,C0800, U0428, and U0452 set in the vehicle. Check the body control module ground at the G218 location. The front dash insulator mat may be trapped between the ground eyelet and the body stud. Remove the round nut and eyelet and cut the front dash insulator mat away from the ground stud so it no longer interferes with the ground stud and reinstall the eyelet and ground nut.
- [10113869](https://open.wenmarpro.com/bulletins/10113869), 2017-08-15: This Preliminary Information communication provides information to the technician about vehicle with Service ABS and/or Traction control lights/message on, Service Power Steering System, Service Suspension System, and or Loss of communication with EBCM, SWPS, PSCM, and/or SCM. Technician may find Diagnostic Trouble Codes U0077, U0121, U0126, U0131, U0139, U0401, U0415, and/or U0428. Technician should remove the driver and passenger sill plate to gain access to the wire harness. If any open, damaged, or corroded wires should be repaired.
- [10113356](https://open.wenmarpro.com/bulletins/10113356), 2017-08-15: This Preliminary Information communication provides information to the technician about vehicles that have a reduced or loss of power steering assist, steering wheel jerks or kicks back when turning, Service Stabilitrak message with warning chime, engine stall, Instrument Panel Cluster going blank or inoperative, radio/Integrated Center Stack going blank, Heater\-Vent\-Air Conditioning going blank, hood ajar message and/or dome lamps flash when shifting into reverse, alarm sounds when locking doors or door locks cycling, and or wipers continue to run for a short time after turning off and then stop/park in the incorrect location. Technician may find Diagnostic Trouble Codes U0073, U0078, U0029, U0028, U0415, U0140, U0126, U0121, U0101, U0100, C0544, C0710, U1510, B127B, B2605, B3600, C0800, U0428, U0452, U0131, and P0513 set in the vehicle. Check the body control module ground at the G218 location. The front dash insulator mat may be trapped between the ground eyelet and the body stud. Remove the round nut and eyelet and cut the front dash insulator mat away from the ground stud so it no longer interferes with the ground stud and reinstall the eyelet and ground nut. Technician will also inspect the starter solenoid battery cable for shorting out on the starter heat shield. Technician will need to voltage drop the battery cables. The battery should be tested using the GR8. X183 or X133 should be inspected for any broken/loose/backed out terminals.
- [10083324](https://open.wenmarpro.com/bulletins/10083324), 2016-10-21: THIS PRELIMINARY INFORMATION COMMUNICATION PROVIDES INFORMATION TO THE TECHNICIAN FOR A REDUCED POWER MESSAGE, STEERING ASSIST, ENGINE STALL OR THE INSTRUMENT PANEL, RADIO, AND OR HEATER\-VENT\-AIR CONDITIONING GO BLANK WITH MULTIPLE DIAGNOSTIC TROUBLE CODES. IF ANY OF THE FOLLOWING DIAGNOSTIC TROUBLE CODES U0073, U0078, U0029, U0028, U0415, U0140, U0126, U0121, U0101, U0100, C0544, U1510, U0073, B127B, B2605, B3600,C0800, U0428, AND U0452 SET IN THE VEHICLE. CHECK THE BODY CONTROL MODULE GROUND AT THE G218 LOCATION. THE FRONT DASH INSULATOR MAT MAY BE TRAPPED BETWEEN THE GROUND EYELET AND THE BODY STUD. REMOVE THE ROUND NUT AND EYELET AND CUT THE FRONT DASH INSULATOR MAT AWAY FROM THE GROUND STUD SO IT NO LONGER INTERFERES WITH THE GROUND STUD AND REINSTALL THE EYELET AND GROUND NUT. TECHNICIAN SHOULD ALSO INSPECT CONNECTOR X183 AND X133FOR ANY BROKEN, LOOSE, BACKED OUT TERMINALS AND REPAIR AS NECESSARY.