Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
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…
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
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…
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
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…
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
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…
CADILLAC, CHEVROLET, GMC, HUMMER
Reported code forms U0121
GM: LOSS OF HIGH SPEED GMLAN COMMUNICATIONS, INTERMITTENT NO CRANK, IP GAGE FLUCTUATION, INTERMITTENT DOOR LOOK CYCLING, INTERMITTENT CHIME OPERATION, VARIOUS IP WARNING LAMPS ILLUMINATED, TRANSMISSION MAY NOT SHIFT,…
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
GMC: UNABLE TO COMMUNICATE WITH THE EBCM DTC U0121. *NJ VEHICLES EQUIPPED WITH JL4. UPDATED 9/30/08. *PE UPDATED 6/27/11. *PE UPDATED 4/6/12. *PE
CADILLAC, CHEVROLET, GMC
Reported code forms U0121
LOSS OF HIGH SPEED GMLAN COMMUNICATIONS, INTERMITTENT NO CRANK, IPC GAUGE FLUCTUATION, INTERMITTENT DOOR LOCK CYCLING, TRANSMISSION MAY NOT SHIFT, DTCS U0073, U0100, U0101, U0102, U0121, U0140 SET (REPAIR BACKED OUT…