U Codes:

U0001 CAN BUS error
U0002 CAN comm bus perf error
U0003 Network management monitoring
U0100 Lost comm w/ECM
U0121 Lost comm W/ABS
U0140 Lost comm W/BCM
U0141 Lost comm w/LHCM
U0142 Lost comm w/RHCM
U0156 Lost comm w/SPEEDO
U0158 Lost comm w/fuel gauge
U0159 Lost comm w/volt gauge
U0160 Lost comm w/ fuel and volt gauge
U0184 Lost comm w/radio
U0185 Lost comm w/Amp 1
U0186 Lost comm w/ AMP 2
U1016 Loss of ECM Serial Data
U1064 Loss of TSM/FSFM Serial Data to ECM
U1097 Loss of SpeedometerSerial Data to ECM
U1255 Serial Data Error
U1300 ECM Serial Data Low
U1300 Serial Data Low
U1301 ECM Serial Data High
U1301 Serial Data High
U1302 ACC bus perf error
U1401 Lost com w/CB