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P300C on the 2021 Mercedes-Benz Sprinter

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.

Bulletins for this model year that name P300C
LI14.30-N-075882_62025-07-01. Service bulletin. Check engine light active - Fault P3007F1, P3007F2, P300CA8, or P300CA9 present in CDI control unit Complaint Check engine warning light active. The following fault codes may be present in the engine control unit: • P3007F1 Leak detected in intake air system or • P3007F2 Mass air flow malfunction in intake air system (cylinder bank 1) or • P300CA8 Leak detected in intake air system or • P300CA9 Mass air flow malfunction in intake air system (cylinder bank 1) or • P300CA9 and P3007F1: Faults are present simultaneously in the quick test Cause Causes for FC P3007F1 or P300CA8: Faults are set if: • If there is a leakage upstream of the exhaust gas turbocharger (see "Dichtring_Sealant.jpg"). • If the housing intermediate flange at the high-pressure EGR valve (where the exhaust back pressure sensor connects) is carbonized or clogged, or if there is carbonization/incomplete sealing of the high-pressure or low- pressure EGR valves. (See “Gehaeusezwischenflansch_intermediate_flange.jpg” and “verstopfter_Gehaeuse- zwischenflansch_clogged_Intermediate_Flange.jpg.”) • Note: Only relevant if correction value in load range 1 is less than -8%. • If the intake manifold (charge air distribution line) or charge air cooler is carbonized (see "Saugrohr_intake_mani- fold.jpg"). • If engine timing is misadjusted. • There is a defective hot film mass air flow sensor or a hot film mass air flow sensor that is affected by incorrect airflow (this can be due to a clogged or deformed air filter). Refer to the attached file "Luftfilter_air_filter." Cause for FC P3007F2 or P300CA9: Faults are set if: • There is a leak downstream of the exhaust gas turbocharger. • The charge air distribution line (intake manifold) is heavily carbonized (see "Saugrohr_intake_manifold.jpg"). • There is carbonization or incomplete closure of the high-pressure exhaust gas recirculation valve, especially in the housing intermediate flange at the EGR valve (linked to the exhaust back pressure sensor). • There is a defective hot film mass air flow sensor, or it is affected by incorrect airflow due to a clogged or defor- med air filter (see "Luftfilter_air_filter"). Cause of fault code combination P300CA9 AND P3007F1: Faults are set if: • There is carbonization or incomplete closure of the high-pressure exhaust gas recirculation valve, especially in the housing intermediate flange at the EGR valve (linked to the exhaust back pressure sensor). Charleston Plant Identification – VIN 11th Digit “T”: For vehicles produced at the Charleston Plant (identified by “T” in the 11th digit of the VIN) with a production date on or after 12/20/2023: • If fault code P3007F1 or P300CA8 is set and the cause is identified as a loose or mis-installed Clean Air Line from the factory, open an Initial Field Quality (Info Only) case. • Include the current Quick Test and photos showing the Clean Air Line issue. For all other vehicles, continue diagnosis as per the standard instructions. Remedy In the case of fault code P3007F1 or P300CA8: 1) Check for Required ECU Software Update (Applies to P300CA8 only)
LI14.30-N-0758822023-03-03. Service bulletin. Complaint Check engine warning light active. Fault code P300CA8 or P300CA9 "Hot film mass air flow sensor malfunction" is present in engine control unit. Cause a) In the case of fault P300CA8: • Due to incorrectly installed component parts of the clean air line between the air filter box and the exhaust gas turbocharger, it is possible that leaks may occur in the system which subsequently result in air mass faults • A fouled air filter or leaks in the intake or charge air system downstream of the exhaust gas turbocharger may also cause these faults. b) In the case of fault P300CA9: • Computational model for programmed values of air intake, in particular, for the high load mode, calculates this high load correction programmed value incorrectly. This leads to the programmed value drifting too quickly towards the limit. Remedy Install the following add-ons: 18937 for XENTRY 12/2020 18938 for XENTRY 03/2021

2 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.