PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 651 / FMI 18
PACCAR Fault Code P0263: Cylinder 1 – Torque Contribution Too Low
P0263 on PACCAR (Kenworth & Peterbilt) engines means: Cylinder 1 – Torque Contribution Too Low. The failure mode (FMI 18) is “data valid but below normal range (moderately severe)”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2017–2020)
- Fault code
- P0263
- J1939 SPN
- 651
- FMI
- 18 — Data valid but below normal range (moderately severe)
- 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 18 tells the shop the type of failure to test for: data valid but below normal range (moderately severe).
- 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 P1201 — Injector Solenoid Valve Cylinder 1 – Current Too Low or Open Circuit on ECU (D420) Pin (A1) and/or Pin (A2)
- PACCAR Fault Code P1202 — Injector Solenoid Valve Cylinder 1 – Short Circuit Between ECU (D420) Pin (A1) and Pin (A2)
- PACCAR Fault Code P1203 — Injector Solenoid Valve Cylinder 1 – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (A1)
- PACCAR Fault Code P1204 — Injector Solenoid Valve Cylinder 1 – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (A1)
- PACCAR Fault Code P1263 — Cylinder 1 – Torque Contribution Too High
- PACCAR Fault Code P1201 — Injector Solenoid Valve Cylinder 1 – Current Too Low or Open Circuit on ECU (D420) Pin (A1) and or Pin (A2)
- Cummins Fault Code 311 — Injector Solenoid Valve Cylinder #1 Circuit – grounded circuit
- Cummins Fault Code 322 — Injector Solenoid Valve Cylinder #1 Circuit - open circuit
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.