PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 91 / FMI 3
PACCAR Fault Code U17A1: Accelerator Pedal 2 – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (B45)
U17A1 on PACCAR (Kenworth & Peterbilt) engines means: Accelerator Pedal 2 – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (B45). The failure mode (FMI 3) is “voltage above normal, or shorted to high source”.
Code details
- Manufacturer
- PACCAR (Kenworth & Peterbilt)
- Applies to
- PACCAR MX-13 (2017–2020)
- Fault code
- U17A1
- J1939 SPN
- 91
- FMI
- 3 — Voltage above normal, or shorted to high 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 3 tells the shop the type of failure to test for: voltage above normal, or shorted to high 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 P0121 — Accelerator Pedal – Sticking Pedal
- PACCAR Fault Code U1703 — Remote Pedal – Voltage Too Low or Short Circuit to Ground
- PACCAR Fault Code U177B — Accelerator Pedal 1 – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (B41)
- PACCAR Fault Code U177C — Accelerator Pedal 1 – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (B41)
- PACCAR Fault Code U177D — Accelerator Pedal Sensor 1 Duty Cycle – Data Valid But Too High on ECU (D420) Pin (B41)
- PACCAR Fault Code U177E — Accelerator Pedal Sensor 1 Duty Cycle – Data Valid But Too Low on ECU (D420) Pin (B41)
- PACCAR Fault Code U177F — Accelerator Pedal 1 Frequency – Data Valid But Too High on ECU (D420) Pin (B41)
- PACCAR Fault Code U17A0 — Accelerator Pedal 1 Frequency – Data Valid But Too Low on ECU (D420) Pin (B41)
Source: PACCAR MX-13 2017–2020 fault code list (Diesel Laptops). See also OBD-II codes.