Mercedes-Benz bulletin LI49.20-N-079157
What it saysComplaint The check engine light is activated, accompanied by one or more of the following fault codes related to the Adblue System: P20F409: The Adblue consumption is too low. NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a service bulletin dated May 19, 2025, received May 2, 2025, about the engine — 2 documents under this number. It names 7 model years (2019–2024). A service bulletin is not a safety recall: it is the manufacturer telling its dealers how to diagnose or repair a condition, and whether the work is paid for depends on the warranty in force. Quoting the number at a service desk can save a diagnosis.
Get the next Mercedes-Benz Sprinter bulletin by email Weekly, only when something new is filed. Nothing else; one-click unsubscribe.
What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationComplaint The check engine light is activated, accompanied by one or more of the following fault codes related to the Adblue System: •P20F409: The Adblue consumption is too low. There is a component fault. •P202E84: The Adblue metering valve 1 (Motor side) has a malfunction. There is a signal below the permissible limit value. Cause The potential causes for these fault codes are: A. A leak in the Adblue System B. An internal fault with the Adblue Injection Valve #1 (Motor side) C. An air pocket forming in the Adblue Injection Valve #1 (Motor side) Adblue Injector Line Remedy --Prior To Production Date 08/01/2024 Code XY4 = MY24-- A. A Leak in the Adblue System 1. Complete the Guided Tests for P20F409 or P202E84: •Perform a thorough inspection of the Adblue Tank, the Adblue Pump, the Adblue Line, and both Adblue Injectors for leaks. •Ensure the Adblue line is properly installed, securely fastened in all clips, and not in contact with the exhaust system. •Remove both Adblue Injection Valves and complete 2-3 pressure build-ups and inspect for Adblue leakage. •If a leak is identified, repair it and retest. B. An internal fault with the Adblue Injection Valve #1 (Motor side) 1. Process Other Fault Codes First: •If there are other fault codes for the Adblue Injection Valves, address these first. •If the Adblue Injection Valve #1 (engine side) fails the guided tests, replace it and retest. C. An air pocket forming in the AdBlue Line (Motor side) 1. If Guided Tests Pass and No Leaks are Found: •Do not replace any components. •Germany has identified the root cause of fault code P20F409 and is working on a solution. The design of the MY23-24, Code XY4 = MY24, OM654 AdBlue Line (A907 470 01 01) is causing air pockets in the system, resulting in fault code P20F409. Depending on the size of the air pocket, you may also encounter fault code P202E84 AdBlue Metering Valve 1 (Motor side). •The guided tests for fault code P20F409 have been updated to include the resetting of learned values for component ‘A103m1 (AdBlue delivery pump)’ and to release the vehicle back to the client.
Documents filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| LI49.20-N-079157 | Service bulletin | May 19, 2025 | 11018922 | PDF, 41 KB |
| LI49.20-N-079157 | Service bulletin | Apr 17, 2025 | 11017567 | PDF, 40 KB |
What the document itself lists
Parts the bulletin names
| Part number | Description | Qty | Find it |
|---|---|---|---|
| A907 470 01 01 | MY23-24 Part X | — | eBay Motors → |
| A907 470 33 02 | MY25 as of August 1, 2024 X | — | eBay Motors → |
Read by machine from the document NHTSA serves (3 pages), read Sep 30, 2026. A part number is shown only where it matches Mercedes-Benz’s own catalogue shape, an operation only with its code and time, and a description only where the reader got it whole; anything it could not settle is left out, and the PDF is the record. Times are the manufacturer’s warranty allowances, not a quote. Listings and prices on eBay Motors are the seller’s.
Affiliate disclosure: some links on this page are affiliate links. If you request a quote or buy through them we may earn a commission at no extra cost to you. Nothing on this page changes because of it.
The summary is NHTSA’s abstract of the document, as filed under 49 CFR 579.5. One communication is usually filed as several documents — the bulletin, a dealer notice, an owner letter — and the number on any of them finds this page. A PDF link is shown only once NHTSA’s own server has been seen to serve that document; the rest are checked over the following nights. Quote the number at a service desk; it is what the dealer’s system is keyed on.
Model years it names
Source: as the manufacturer filed themAlso filed against model years this site has no page for: 2024 Mercedes-Benz Esprinter.
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
Email me new Mercedes-Benz bulletins for the Sprinter
A weekly email, sent only in a week when Mercedes-Benz files something new with NHTSA for the model you pick — service bulletins, campaigns, warranty extensions, over-the-air notices, every model year. Nothing else is sent; one-click unsubscribe in every message. Separate from recall alerts.
What owners reported
Source: NHTSA complaint databaseOwners of the 6 model years this bulletin names have filed 385 complaints with NHTSA since 2015. 48 of them name Engine — the same broad component group this bulletin is filed under. NHTSA groups complaints coarsely, so that means the same area of the vehicle, not necessarily the same fault.
on 08-03=23, I as driving MB sprinter van on highway Route 84 east toward Connecticut, when I was near Southington exit smoke was coming out of AC vent, I took exit to route 10 and stopped van right after exit on the road, and opened hood, there was active fire near lower left side engine, with help of drivers who stopped behind me, I…
2020 Mercedes-Benz Sprinter · Engine · filed with NHTSA Aug 22, 2023 · ODI 11539986
The ECM harness was wired too close to a sharp metal piece within the engine bay, the clip MBZ uses to secure it was insufficient to hold it back, the thick wiring harness got caught on the metal piece and overtime got cut deeply causing a short with thermal issues spreading to other components, the wiring harness melted together and…
2023 Mercedes-Benz Sprinter · Engine · filed with NHTSA Oct 8, 2026 · ODI 11769942
Complaint Description I am filing this complaint with the National Highway Traffic Safety Administration regarding a safety issue with my new Mercedes Benz Sprinter 2500. I purchased this vehicle brand new from Mercedes Benz Manhattan. From the first day of ownership, I began experiencing multiple serious problems with the van.
2024 Mercedes-Benz Sprinter · Engine · filed with NHTSA Mar 15, 2026 · ODI 11724480
A complaint is one owner’s account, not a defect finding, and a bulletin is not a recall. Nothing here says this bulletin was issued because of these complaints, or that the repair it describes fixed them. Complaint files on this site begin in 2015.
More bulletins about the engine
Source: same model, same component group32 other manufacturer communications filed against these Mercedes-Benz models under the same component group (engine), newest first. The eight newest are listed; the rest are on the Mercedes-Benz list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| LI20_10-N-080868_2_en | Service bulletin | Sep 2, 2026 | Coolant warning light (MIL) lights up on the display Complaint The coolant warning lamp may be displayed in the instrument cluster. The malf… |
| LI09_41-N-079165_2_en | Service bulletin | Aug 3, 2026 | Complaint Low Coolant warning with possible engine misfire caused by a leaking Charge Air Cooler (Intercooler), accompanied by one or more o… |
| LI07.16-N-080731 | Service bulletin | Jun 18, 2026 | Complaint The customer reports an exhaust odor from the engine compartment, potentially accompanied by a check engine light and/or engine mi… |
| LI14.20-N-073867 | Service bulletin | Jun 15, 2026 | Complaint Complaint A: The engine is jolting/bucking between 1700 and 1900 rpm. Complaint B: One or more mechanical related fault codes for… |
| LI09.41-N-080666 | Service bulletin | Jun 3, 2026 | Check engine light with reduced power –P300A6D due to charge air system contamination Complaint The check engine light is activated, accompa… |
| LI05.30-N-080518 | Service bulletin | Jun 3, 2026 | OM654 Extended engine crank or starting concerns and/or poor running characteristics Complaint One or more of the following may be reported:… |
| LI4910-N-060969 | Service bulletin | Apr 18, 2026 | Complaint Rattling noise from underneath the vehicle. Cause One or more of the following conditions may be present: 1. The exhaust bracket f… |
| LI49.20-N-075995 | Service bulletin | Mar 23, 2026 | Vehicles with SCR Generation 4: SCR/AdBlue® warning message cannot be reset with fault code P13DF00 or P300685 Complaint SCR or AdBlue warni… |
Quote the number at the service desk. It is what the dealer’s system is keyed on.
Every manufacturer communication NHTSA holds for Mercedes-Benz, by the number printed on the letter.
Common questions
Source: NHTSA, 49 CFR 579.5Is Mercedes-Benz LI49.20-N-079157 a recall?
No. A service bulletin is a manufacturer communication filed with NHTSA under 49 CFR 579.5; a safety recall carries an NHTSA campaign number (two digits, a letter, six digits) and a federal duty to repair for free. Check the vehicle’s recalls by VIN at nhtsa.gov/recalls, or on its page here.
Is the LI49.20-N-079157 repair free?
Not automatically. A service bulletin describes how to diagnose or repair a condition; who pays depends on the warranty in force, any extension, and the dealer. Quoting the number can save a diagnosis either way. Every Mercedes-Benz warranty extension on file lists the ones Mercedes-Benz has filed.
Which vehicles does LI49.20-N-079157 cover?
The manufacturer filed it against 7 model years: 2024 Mercedes-Benz Sprinter, 2023 Mercedes-Benz Sprinter, 2022 Mercedes-Benz Sprinter, 2021 Mercedes-Benz Sprinter, 2020 Mercedes-Benz Sprinter, 2019 Mercedes-Benz Sprinter and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.