PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 4376 / FMI 4
PACCAR Fault Code P3845: Sensor Circuit PM Sensor – Voltage Too High
P3845 on PACCAR (Kenworth & Peterbilt) engines means: Sensor Circuit PM Sensor – Voltage Too High. 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 (2017–2020)
- Fault code
- P3845
- J1939 SPN
- 4376
- 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 P3845 — Pump Module Reverting Valve – Voltage Too Low or Short Circuit to Ground on ECU (D374) Pin (B34)
- PACCAR Fault Code P3846 — PM Sensor ECU – Internal Error
- PACCAR Fault Code P3911 — Heater Element DEF Inlet Pipe – Voltage Too Low or Short Circuit to Ground on ECU (D442) Pin (26)
- PACCAR Fault Code P3846 — Pump Module Reverting Valve – Short Circuit to Supply or Open Circuit on ECU (D374) Pin (B34)
- PACCAR Fault Code P3911 — Pump Module Reverting Valve – Malfunction
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.