PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 5747 / FMI 4
PACCAR Fault Code P3803: PM Sensor – Voltage Too Low or Short Circuit to Ground
P3803 on PACCAR (Kenworth & Peterbilt) engines means: PM Sensor – Voltage Too Low or Short Circuit to Ground. The failure mode (FMI 4) is “voltage below normal, or shorted to low source”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2013–2016)
- Fault code
- P3803
- J1939 SPN
- 5747
- FMI
- 4 — Voltage below normal, or shorted to low source
- 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 4 tells the shop the type of failure to test for: voltage below normal, or shorted to low source.
- 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 P3803 — CAN Communication – Time-Out From PM Sensor
- PACCAR Fault Code P3760 — Exhaust Gas Temperature Before DOC – Data Valid But Too High, at Ignition ON
- PACCAR Fault Code P3761 — Exhaust Gas Temperature Before DPF – Data Valid But Too High, at Ignition ON
- PACCAR Fault Code P3759 — Heater Element PM Sensor – Voltage Too High or Short Circuit to Supply, High Side
- PACCAR Fault Code P3760 — Heater Element PM Sensor – Voltage Too Low or Short Circuit to Ground, High Side
- PACCAR Fault Code P3761 — Heater Element PM Sensor – Voltage Too High or Short Circuit to Supply, Low Side
- International Fault Code SPN 5747 FMI 10 — Aftertreatment 1 Outlet Soot Sensor Heater: Abnormal Rate Of Change
- International Fault Code SPN 5747 FMI 3 — Aftertreatment 1 Outlet Soot Sensor Heater: Voltage Above Normal, Or Shorted To High Source
Source: PACCAR MX-13 2013–2016 fault code list (Diesel Laptops). See also OBD-II codes.