PACCAR (Kenworth & Peterbilt)
PACCAR fault code
SPN 1696 / FMI 4
PACCAR Fault Code P2238: Lambda – Current Too Low on ECU (D420) Pin (C45)
P2238 on PACCAR (Kenworth & Peterbilt) engines means: Lambda – Current Too Low on ECU (D420) Pin (C45). 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
- P2238
- J1939 SPN
- 1696
- 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
Source: PACCAR MX-13 2013–2016 fault code list (Diesel Laptops). See also OBD-II codes.