PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 1668 / FMI 9
PACCAR Fault Code U1134: CAN – Message (A1SCRDSR2) Time-Out From Aftertreatment System
U1134 on PACCAR (Kenworth & Peterbilt) engines means: CAN – Message (A1SCRDSR2) Time-Out From Aftertreatment 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
- U1134
- J1939 SPN
- 1668
- 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 P30B3 — CAN – Message (AT1IG1) Time-Out From NOx Sensor Before Catalyst
- PACCAR Fault Code U0105 — CAN – Message (TESTRUN_INFO) Time-Out From Aftertreatment System
- PACCAR Fault Code U1015 — CAN Communication – Hardware or Software Malfunction on A-CAN
- PACCAR Fault Code U1016 — CAN – Message (A1DOC) Time-Out From Aftertreatment System
- PACCAR Fault Code U1112 — CAN – Message (SCR1) Time-Out From Aftertreatment System
- PACCAR Fault Code U1114 — CAN – Message (AT1T1I) Time-Out, DEF Tank Information From Aftertreatment System
- PACCAR Fault Code U111D — CAN – Message (EXH_GAS_CORR) Time-Out From Aftertreatment System
- PACCAR Fault Code U113A — CAN – Message (AT1HI) Time-Out From Aftertreatment System
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.