Mercedes-Benz bulletin LI83.90-P-080935
What it saysComplaint CEL illuminates and/or AC does not blow cold. NHTSA’s full summary ↓
Mercedes-Benz filed this with NHTSA as a service bulletin dated Sep 25, 2026, about the visibility/wiper. It names 26 model years (2021–2027). 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.
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What the bulletin says
Source: NHTSA's summary of the manufacturer's communicationComplaint CEL illuminates and/or AC does not blow cold. Cause Potentially relevance to hardware and/or software Remedy Scenario 1: 1. If the AC does not blow cold air, replace compressor (if compressor's index and part number Figure 1 match against Table 1). a. If the compressor does not fall within Table 1, please open a TIPS case. b. Flush procedure must be followed as per WIS. Scenario 2: 1. If AC does blow cold. a. Follow the following procedure: i. Have the air conditioning system recharged. ii. Clear the fault codes afterward. iii. Let the vehicle stand for 8 hours (OBD reset condition). iv. Check whether the fault is still present. b. Open TIPS case with your findings and answers the following questions, send to the HV/LV inbox. i. When exactly did the MIL appeared (immediately at start‑up or while driving). ii. What was the ambient temperature, any special driving maneuvers, and whether the vehicle had just come out of a climate‑controlled garage.
Document filed under this number
| Document | Kind | Dated | NHTSA id | At NHTSA |
|---|---|---|---|---|
| LI83.90-P-080935 | Service bulletin | Sep 25, 2026 | 11037484 | PDF, 32 KB |
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 AMG C63 S E; 2024 Mercedes-Benz AMG C63 S E 4MATIC+; 2024 Mercedes-Benz AMG S 63 E; 2026 Mercedes-Benz AMG S 63 E 4MATIC+.
A vehicle page’s bulletin list shows the newest few communications filed against that model year; the count there is every one.
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What owners reported
Source: NHTSA complaint databaseOwners of the 22 model years this bulletin names have filed 345 complaints with NHTSA since 2015. 4 of them name Visibility/Wiper — 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.
While on the freeway, going approximately 70 mph, the vehicles onboard cameras all failed and I got a warning that said “camera dirty/unavailable/traffic sign assist currently unavailable”. Because of this failure, I almost crashed the car in Front of me. I cleaned all the cameras. The message continues to appear.
2021 Mercedes-Benz S-Class · Visibility/Wiper · filed with NHTSA Jan 18, 2025
I am reporting a safety defect involving the panoramic sunroof on my 2021Mercedes-Benz Coop vehicle. The panoramic sunroof has malfunctioned due to an apparent design or manufacturing defect. The sunroof fails to open / close and makes grinding or popping noises which malfunctioned unexpectedly.
2021 Mercedes-Benz C-Class · Visibility/Wiper · filed with NHTSA Jan 20, 2026
The contact owns a 2024 Mercedes-Benz S 580-E. The contact stated that while driving 80 MPH, there was an explosive sound coming from the vehicle. There was no warning light illuminated. The contact drove to the nearest dealer where it was discovered that the sunroof had exploded without impact.
2024 Mercedes-Benz S-Class · Visibility/Wiper · filed with NHTSA May 27, 2025
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 visibility/wiper
Source: same model, same component group12 other manufacturer communications filed against these Mercedes-Benz models under the same component group (visibility/wiper), newest first. The eight newest are listed; the rest are on the Mercedes-Benz list.
| Number | Kind | Dated | NHTSA’s summary |
|---|---|---|---|
| LI83.55-P-080937 | Service bulletin | Sep 1, 2026 | Cause Internal failure of the scroll wheel within the AC compressor. Remedy Check the compressor's index and part number Figure 1 against Ta… |
| PSL-NCU Return Parts 6/19 | Other | Jun 19, 2026 | Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be ret… |
| LI82.30-P-059239 | Service bulletin | May 19, 2026 | Complaint There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper blades squeaking, chatteri… |
| LI83.70-P-080411 | Service bulletin | Apr 13, 2026 | Complaint No heating output is available during electric driving operation. In conventional (combustion engine) driving operation, full heat… |
| LI72.40-P-071889 | Service bulletin | Apr 7, 2026 | Complaint When closing the door, the side window may remain slightly open (short stroke position). Automatic window raising function of side… |
| LI83.30-P-079850 | Service bulletin | Jan 16, 2026 | Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy *… |
| LI83.20-P-079559 | Service bulletin | Jul 18, 2025 | Complaint No cooling output, compressor inoperative. Cause Currently under analyzed. Remedy Please create a TIPS case and provide the follow… |
| LI83.30-P-079081 | Service bulletin | Apr 21, 2025 | Complaint Random heating of air conditioning system. Cause Temperature sensor in overhead control panel (OCP) delivering incorrect values: T… |
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 LI83.90-P-080935 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 LI83.90-P-080935 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.
Which vehicles does LI83.90-P-080935 cover?
The manufacturer filed it against 26 model years: 2026 Mercedes-Benz AMG GT, 2025 Mercedes-Benz AMG GT, 2024 Mercedes-Benz AMG GT, 2027 Mercedes-Benz C-Class, 2026 Mercedes-Benz C-Class, 2025 Mercedes-Benz C-Class and more. Whether one particular vehicle is affected is a matter of its VIN and its build, not its model year alone.