PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 103 / FMI 16
PACCAR Fault Code P1581: Turbocharger Speed – Data Valid But Too Low
P1581 on PACCAR (Kenworth & Peterbilt) engines means: Turbocharger Speed – Data Valid But Too Low. The failure mode (FMI 16) is “data valid but above normal range (moderately severe)”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2017–2020)
- Fault code
- P1581
- J1939 SPN
- 103
- FMI
- 16 — Data valid but above 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 16 tells the shop the type of failure to test for: data valid but above 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 P1581 — Turbo Speed – Data Valid But Too Low
- PACCAR Fault Code P102C — VTG Turbocharger Turbine – Malfunction
- PACCAR Fault Code P1580 — Turbocharger Speed – Data Valid But Too High
- PACCAR Fault Code P2579 — Turbocharger Speed – Abnormal Rate of Change
- PACCAR Fault Code P2580 — Turbocharger Speed – Data Valid But Too Low, Least Severe on ECU (D420) Pin (C20)
- PACCAR Fault Code P2581 — Turbocharger Speed – Data Valid But Too High, Least Severe on ECU (D420) Pin (C20)
- PACCAR Fault Code P0049 — Turbo Speed – Higher than Overspeed Limit
- PACCAR Fault Code P1235 — Turbo Speed – Data Erratic, Intermittent, or Incorrect
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.