PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 5571 / FMI 15
PACCAR Fault Code P109D: Common Rail Pressure Release Valve – Current Too High on ECU (D420) Pin (C4)
P109D on PACCAR (Kenworth & Peterbilt) engines means: Common Rail Pressure Release Valve – Current Too High on ECU (D420) Pin (C4). The failure mode (FMI 15) is “data valid but above normal range (least severe)”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2017–2020)
- Fault code
- P109D
- J1939 SPN
- 5571
- FMI
- 15 — Data valid but above normal range (least 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 15 tells the shop the type of failure to test for: data valid but above normal range (least 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 P009F — Common Rail Pressure Release Valve – Malfunction Detected During Check
- PACCAR Fault Code P2294 — Common Rail Pressure Release Valve – Open Circuit on ECU (D420) Pin (C4) or Pin (C26)
- PACCAR Fault Code P2295 — Common Rail Pressure Release Valve – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (C4)
- PACCAR Fault Code P229A — Common Rail Pressure Release Valve Current – Too High
- PACCAR Fault Code P229B — Common Rail Pressure Release Valve Current – Too Low
- PACCAR Fault Code P229C — Common Rail Pressure Release Valve Current – Data Valid But Too Low
- PACCAR Fault Code P229D — Common Rail Pressure Release Valve Current – Data Valid But Too High
- PACCAR Fault Code P109C — Common Rail Pressure Release Valve – Current Too Low or Open Circuit on ECU (D420) Pin (C4)
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.