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Service bulletins for the 2021 Freightliner Sprinter

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

87 on file from NHTSA, as of 2026-10-19.

About P300E on the 2021 Freightliner Sprinter: what the code means, and the bulletins and recalls about the same components.

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Only bulletins with trouble code: P300E are shown. Show all

Bulletins, newest first
LI49.20-N-0765652025-08-01. Service bulletin. UNKNOWN OR OTHER. Check engine light with fault code P300E3B in the CDI control unit CDI (N3/28) Complaint Check engine light is illuminated with fault code P300E3B “The efficiency of component 'SCR catalytic converter' is not sufficient" stored in the CDI control unit (N3/28). Cause Excessive ammonia slip is being detected in the SCR system, often triggered by IUMPR (In-Use Monitor Performance Ratio) thresholds. This typically indicates that the SCR catalyst is not converting DEF (AdBlue) efficiently under moni- tored conditions. Common Driving Scenario: •Non-dynamic driving (e.g., highway cruising with cruise control set) •Minimal load changes, steady-state exhaust flow Contributing Factors: •Software influence – IUMPR (In-Use Monitor Performance Ratio) thresholds •DEF Overdosing – Over-injection due to faulty NOx sensors, dosing valve issues, or poor DEF quality •Low Exhaust or Catalyst Temperatures – Common under low-load conditions; reduces SCR conversion efficiency •Catalyst Degradation or Contamination – Aging catalyst or contamination from oil, coolant, or poor-quality DEF Remedy IMPORTANT: Do not replace any components unless instructed through TIPS. For Model Year 2019–2021 Vehicles: •Update the following control units to the latest available software: N3/28 – Motor Electronics 'CDI61NFZ' for combustion engine 'OM642' (CDI):
LI14.20-N-079253_32025-07-01. Service bulletin. ENGINE. Check engine light with fault code P300E55 with H12 Complaint The check engine light is activated, accompanied by the following fault code related to the Exhaust gas recirculation cooler (low pressure): •P300E55 The efficiency of component 'Exhaust gas recirculation cooler (low pressure)' is not sufficient. Cause The issue is attributed to an error in the coding of the climate control unit software (HVAC177). Remedy Software Update Instructions Please proceed as follows for the different variants:
LI14.20-N-0792532025-06-03. Service bulletin. ENGINE. Complaint The check engine light is activated, accompanied by the following fault code related to the Exhaust gas recirculation cooler (low pressure): •P300E55 The efficiency of component 'Exhaust gas recirculation cooler (low pressure)' is not sufficient. Cause The issue is attributed to an error in the coding of the climate control unit software (HVAC177). Remedy A software update to correct the coding error is currently in the process of release for the Aftersales network. In the interim, please proceed as follows: •Erase the fault memory (DTCs) from the control unit. •Return the vehicle to the customer. •No further diagnostic or repair procedures are required at this time.
LI49.20-N-0765652024-11-05. Service bulletin. UNKNOWN OR OTHER. Complaint: Check engine light with fault code: P300E3B the efficiency of component 'SCR catalytic converter' is not sufficient, is present in the CDI control unit CDI (N3/28). Cause: This subject is currently being analyzed for all 907s equipped with the OM642 engine. Follow the instructions related to this subject to collect information about your vehicle. After completing the checks, please open a TIPS case and at-tach the collected information.
LI49.20-N-0765652024-10-08. Service bulletin. UNKNOWN OR OTHER. Complaint Check engine light with fault code: P300E3B the efficiency of component 'SCR catalytic converter' is not sufficient, is present in the CDI control unit CDI (N3/28). Cause This subject is currently being analyzed for all 907s equipped with the OM642 engine. Follow the instructions related to this subject to collect information about your vehicle. After completing the checks, please open a TIPS case and attach the collected information. Remedy Please complete the following inspections and tests: 1. Perform a tailpipe wipe test and document the results along with photographs. 2. Inspect the NOx connectors, pins, crimps, and harnesses between N37/7 and N37/8 to F152f59, Z7108, W105/3, and X30/81. 3. Provide actual values/sensor plausibility test results for all pressure and temperature sensors with the engine com- pletely cooled off for at least eight hours, the key on, and the engine off. Repeat the test with the engine/exhaust at operating temperature and the engine idling. 4. Perform a pressurized smoke test of the intake, charge air system, and exhaust to verify that there are no leaks. Apply overpressure (not exceeding 26 psi) from the exhaust pipe end and seal the system at the clean airline toward the air filter housing. Manipulate all components during the smoke test. 5. Provide diesel particulate filter actual values and regeneration history. 6. Inspect the SCR temperature sensor wirings and pins for electrical and physical correctness. Determine whether this sensor reaches operating temperature while driving and document the time it takes to reach operating temperatu- re. 7. Inspect the Adblue injector nozzle/s for clogging or leaking, and provide photographs. 8. With the Adblue injector/s removed from the exhaust system, perform two to three Adblue pressure tests and check for leaks. If leaks are detected, provide photographs. 9. Collect an Adblue sample, test fluid quality, and provide notes on its condition and quantity (color, clarity, separati- on, odor, etc.), along with a photograph for review. Also, provide a photograph of the spray pattern. 10. Separate the exhaust pipe downstream of the diesel particulate filter, inspect the diesel particulate filter and SCR, and note any soot, blockage, or damage. Provide photographs. 11. Inspect the SCR catalyst interior for dried Adblue residue, and provide photographs. 12. Perform several test drives at varying speeds to gather graphical illustrations (screenshots of the completed graphs in PDF format) of signals from NOx sensors. Provide three to four graphs or actual values of operational NOx sensors with XENTRY; see attachments for examples. Additionally, provide one graph/screenshot of the vehicle idling at operating temperature. Disconnect the Adblue injection valve, drive for approximately 30 minutes to exhaust all Ad- blue within the SCR catalytic converter, and provide two to three additional NOx graphs/screenshots with the sensor disconnected. (see attachments for needed graphs)

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.