PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 1235 / FMI 9
PACCAR Fault Code U1120: CAN – Message (TSC1_BE) Time-Out From Brake System
U1120 on PACCAR (Kenworth & Peterbilt) engines means: CAN – Message (TSC1_BE) Time-Out From Brake System. The failure mode (FMI 9) is “abnormal update rate”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2017–2020)
- Fault code
- U1120
- J1939 SPN
- 1235
- FMI
- 9 — Abnormal update rate
- Truck models in source
- Kenworth T680, T880, W900, T800; Peterbilt 579, 389, 567, 367
What to do next
- Read active and inactive codes with the OEM service tool and note the occurrence count.
- FMI 9 tells the shop the type of failure to test for: abnormal update rate.
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
- PACCAR Fault Code U0141 — CAN – Message (TCO1) Time-Out From Tachograph
- PACCAR Fault Code U0157 — CAN – Message (AMB) Time-Out From Vehicle Control System
- PACCAR Fault Code U1014 — CAN Communication – Hardware or Software Malfunction on V-CAN1
- PACCAR Fault Code U1110 — CAN – Message (RC_DR) Time-Out From Retarder System
- PACCAR Fault Code U1138 — CAN – Message (TSC_AE) Time-Out From Brake System
- PACCAR Fault Code U1144 — CAN – Message (TD) Time-Out From Tachograph
- PACCAR Fault Code U1208 — CAN – Message (PTO) Time-Out From Vehicle Control System
- PACCAR Fault Code U1721 — CAN – Message (VEP1) Time-Out From Aftertreatment System
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.