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Service bulletin LI83.20-P-079559

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.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11020874
Published by NHTSA2025-07-24
Manufacturer's numberLI83.20-P-079559
Manufacturer's date2025-07-18
NHTSA componentVISIBILITY/WIPER

NHTSA's summary

Complaint No cooling output, compressor inoperative. Cause Currently under analyzed. Remedy Please create a TIPS case and provide the following information: -Provide the refrigerant filling capacity -Current actual values from XENTRY (compressor values) -Has there previously been work on the refrigerant circuit in the vehicle? -Check air conditioning system for leak tightness as per WIS -Document results and possible leaks in TIPS case

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Glass, wipers and mirrors, Wipers and washers

Vehicles listed
MERCEDES-BENZ AMG CLS532019 to 2021
MERCEDES-BENZ AMG E432018
MERCEDES-BENZ AMG E532019 to 2023
MERCEDES-BENZ AMG E63 S2023
MERCEDES-BENZ AMG E63S2018 to 2021
MERCEDES-BENZ AMG GT432021, 2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ AMG GT532019, 2020, 2021, 2022, 2023 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ AMG GT632020, 2021 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ AMG GT632023, 2024 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ AMG GT63 S2023 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ AMG GT63S2020, 2021 (the catalog's model; the bulletin names a series or trim of it)
MERCEDES-BENZ CLS 4502019 to 2021
MERCEDES-BENZ E 3002018 to 2019
MERCEDES-BENZ E 3502020 to 2023
MERCEDES-BENZ E 4002018
MERCEDES-BENZ E 4502019 to 2023
MERCEDES-BENZ E3002017

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
LI83.90-P-0809352026-09-25. Service bulletin. Complaint 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.
PSL-NCU Return Parts 6/192026-06-25. Other. Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, July 9, 2026. After July 9th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below.
LI82.30-P-0592392026-05-20. Service bulletin. Complaint There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper blades squeaking, chattering, shuddering B: The windshield is not wiped completely (streaking) C: During the downward movement water is pulled back onto the windshield from the A-pillar (Figure 1) D: After windshield cleaning, water keeps spraying onto the windshield for several wipe cycles (Figure 2) A1: The windshield and wiper blades are contaminated with residues from car washing facilities, identifiable by the water beading. The resulting differences in the friction values between the wiper blades and the windshield can excite the wiper blades to vibrate. Note: It is mostly wax residue from the washer system, but also water-repellent nano-particle coating for paint and/or silicone-based washer fluid, that could cause this problem. A partially dry windshield also has different friction values, which can likewise result in squeaking of the wiper blades A2: The wiper blades are worn by mechanical damage (wiper lip damaged by ice or insect debris, or deformed by long periods of disuse). A3: Incorrect angle of incidence of the wiper arms to the windshield. Because of this, the rubber lip of the wiper blade may not flip over at the reversal point. Cause B: B1: Wax/ dirt residues on the windshield B2: Wiper blades deformed or worn B3: Downforce of wiper arm not OK (Figure 3) Cause C: Water is pulled back onto the windshield by the differential pressure created as the wiper arm moves downwards. Cause D: Washer water collects in the fastening of the wiper blade and is blown onto the windshield by the airstream over several wipe cycles. Note and supporting information: Wiper blades are wear parts which, even when "not used" for long periods (kept in park position), may become permanently deformed and damaged. Further stresses on the rubber wiper blade arise due to various environmental influences which progressively change the effectiveness of the rubber wiper blade and accelerate the aging process. Due to the natural aging process and wear, the wiper blades should be replaced twice a year, preferably in Spring and Fall (see operator's manual). Remedy Remedy A: A1: Cleaning entire windshield with A 000 986 40 71. A2: Checking water's flow behavior after windshield has been cleaned (see Video 1). If, after cleaning, there are still areas with water beading, then the cleaning process must be carried out again until a rejection reaction is no longer present. • Note: On the vehicle in the video (Video 1), water still beads on the bottom left of the windshield. The windshield is still not properly clean, even though it appears to be clean. The windshield is only properly clean when there are no more areas on the windshield where water beads. A3: Replace wiper blades with genuine wiper blades. Important: Only exchange wiper blades if windshield no longer has water-repellent areas Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. Remedy B: B1: Clean windshield with intensive cleaner A 000 986 40 71. Important: Do not clean the wiper blades otherwise the graphite coating will be damaged. B2: Replace wiper blades with genuine wiper blades • Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. B3: Check the wiper arm for excessive resistance in the bearing. Restore mobility or replace wiper arm if necessary. Remedy C: Problem inherent in design for which there is no technical remedy. Exception: X204 up to 02/2014. In these vehicles, it is possible to install the design configuration of vehicles as of 02/2014. This includes wiper arms (styled arms) with improved behavior in this respect. It is also necessary to replace the wiper blades because the styled arms feature a Top Lock connection (previously Side Lock).
LI83.30-P-0798502026-01-22. Service bulletin. Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy *Note - This Li does not apply if there are other Li's that apply to your concern OR you have a fault and/or guided test that leads to a root cause. AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle • Determine if the behavior is normal by comparing with a similar vehicle. Determine Your Game and Players • Identify the diagnostic strategy and involved components/systems. Testing • Perform relevant diagnostic tests. Refrigerant Quantity • Record the amount of refrigerant recovered and compare it to the specified value (if applicable). • Forming Gas is the ONLY approved leak test method. (DYE is NOT approved) TIPS Case Submission Requirements/Warranty Claim Submission Requirements (Template attached to be used for submission of Warranty claim and/or TIPS case) Cooling Capacity Test (If System Has a Charge) *Note - TIPS case is only required if the root cause is not identified or other Li's/documents require a case to be open. Before Repairs Gauge Readings • High and Low pressure readings (from machine or separate gauges). Leak Detection (if applicable) • PPM of any leaks found. XENTRY Printouts • Climate control AVs. • HV compressor AVs (for heat and AC systems). Thermometer Readings • Left and right dash vents. • Center vent, footwell, and/or rear vents (if concern is localized). Ambient Conditions • Temperature and humidity from OCP AVs (if available). After Repairs Gauge Readings • High and Low pressure readings before and after repairs. Thermometer Readings • Left and right dash vents before and after. • Center vent, footwell, and/or rear vents before and after (if localized concern). Documentation • Complaint Analysis, Game/Players, and Testing Steps. • Include expected results and technical justification for the diagnosis. • Avoid listing R/I steps—focus on diagnostic reasoning and root cause. • All prior measurements need to be documented on the repair order. OP code usage: 831232 - Max .5 for Cooling Capacity Test 831040 - Only to be utilized if you have a fault code and are actively diagnosing that fault code (MAX 1 hour) 831762 - This includes basic leak check 831285 - This can only be used in extenuating circumstances where a leak cannot be found (MAX 1 hour)
LI83.30-P-0798502026-01-16. Service bulletin. Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle • Determine if the behavior is normal by comparing with a similar vehicle. Determine Your Game and Players • Identify the diagnostic strategy and involved components/systems. Testing • Perform relevant diagnostic tests. Refrigerant Quantity • Record the amount of refrigerant recovered and compare it to the specified value (if applicable). • Forming Gas is the ONLY approved leak test method. (DYE is NOT approved) TIPS Case Submission Requirements/Warranty Claim Submission Requirements Cooling Capacity Test (If System Has a Charge) *Note - TIPS case is only required if the root cause is not identified or other Li's/documents require a case to be open. Before Repairs Gauge Readings • High and Low pressure readings (from machine or separate gauges). Leak Detection (if applicable) • PPM of any leaks found. XENTRY Printouts • Climate control AVs. • HV compressor AVs (for heat and AC systems). Thermometer Readings • Left and right dash vents. • Center vent, footwell, and/or rear vents (if concern is localized). Ambient Conditions • Temperature and humidity from OCP AVs (if available). After Repairs Gauge Readings • High and Low pressure readings before and after repairs. Thermometer Readings • Left and right dash vents before and after. • Center vent, footwell, and/or rear vents before and after (if localized concern). Documentation • Complaint Analysis, Game/Players, and Testing Steps. • Include expected results and technical justification for the diagnosis. • Avoid listing R/I steps—focus on diagnostic reasoning and root cause. • All prior measurements need to be documented on the repair order. OP code usage: 831232 - Max .5 for Cooling Capacity Test 831040 - Only to be utilized if you have a fault code and are actively diagnosing that fault code (MAX 1 hour) 831762 - This includes basic leak check 831285 - This can only be used in extenuating circumstances where a leak cannot be found (MAX 1 hour)
LI83.30-P-0798502026-01-09. Service bulletin. Complaint Customer states the AC either does not cool/has poor performance or heat is insufficient. Cause Many possible root causes Remedy AC Diagnosis (General) Initial Steps Verify Customer Concern • Confirm the issue reported by the customer. Compare to Like Vehicle • Determine if the behavior is normal by comparing with a similar vehicle. Determine Your Game and Players • Identify the diagnostic strategy and involved components/systems. Testing • Perform relevant diagnostic tests. Refrigerant Quantity • Record the amount of refrigerant recovered and compare it to the specified value (if applicable). • Forming Gas is the ONLY approved leak test method. (DYE is NOT approved) TIPS Case Submission Requirements Cooling Capacity Test (If System Has a Charge) Before Repairs Gauge Readings • High and Low pressure readings (from machine or separate gauges). Leak Detection (if applicable) • PPM of any leaks found. XENTRY Printouts • Climate control AVs. • HV compressor AVs (for heat and AC systems). Thermometer Readings • Left and right dash vents. • Center vent, footwell, and/or rear vents (if concern is localized). Ambient Conditions • Temperature and humidity from OCP AVs (if available). After Repairs - Warranty Submission Requirements on the Repair Order Gauge Readings • High and Low pressure readings before and after repairs. Thermometer Readings • Left and right dash vents before and after. • Center vent, footwell, and/or rear vents before and after (if localized concern). Documentation • Complaint Analysis, Game/Players, and Testing Steps. • Include expected results and technical justification for the diagnosis. • Avoid listing R/I steps—focus on diagnostic reasoning and root cause. • All prior measurements need to be documented on the repair order. OP code usage: 831232 - Max .5 for Cooling Capacity Test 831040 - Only to be utilized if you have a fault code and are actively diagnosing that fault code 831762 - This includes basic leak check 831285 - This can only be used in extenuating circumstances where a leak cannot be found
LI82.10-P-0780692024-11-13. Service bulletin. Complaint Rear lamps fogged up/not leaktight. Cause Fogging of the rear lamps is a natural phenomenon, which can occur under certain climatic conditions. This does not lead to any technical impairment of the rear lamps. Remedy Rear lamp: Remedy 1: Clearing fogged/condensed rear lamps: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4 °F) Note: Do not wash the vehicle or subject it to high-pressure cleaning before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the trunk. 4. Switch on the exterior lighting. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation -> a significant reduction in the formation of condensation must be clearly recognizable (defogging progress). Note: -If no reduction in the degree of fogging is visible, the rear lamp is defective and must be replaced. -It is not physically possible to defog the headlamps completely – some residual fogging may remain. Fogging does not impair the functionality or the service life of the rear lamps. -Simultaneous fogging of multiple component parts indicates extreme climatic conditions and also does not impair the functionality or the service life of the rear lamps. Remedy 2: You can recognize a defective rear lamp as follows: 1. Check the rear lamps to ensure that no external damage is present, and that the differential aeration cells and the diaphragm are present and correctly seated. -> If there are signs of external damage on the rear lamp, the component parts must be replaced as per WIS instructions. 2. Check the electrical connectors of the plugs and pins. -> If moisture/corrosion/etc. is present, the component part must be replaced as per WIS instructions. 3. Check for leak tightness -> Close all openings with Terostat IX or similar and establish and stabilize via an overpressure (40–50 mbar) via the plug. -> In the event of a sudden pressure drop, the component part must be replaced as per WIS instructions. Note: External damage to the rear lamps does not constitute a warranty or goodwill case.
LI82.35-P-0784672024-10-25. Service bulletin. Complaint Washer fluid system leaks Cause Various possible causes: 1. Washer fluid reservoir itself. 2. Seal on washer fluid pump/washer fluid reservoir. 3. Washer fluid pump. 3.1. Distributor housing leaks. 3.2. Pump fitting leaks. 3.3. Washer fluid hose cannot be snapped into place on pump fitting. 3.4. Washer fluid hose will not stay on pump fitting, although connector OK. 4. Washer fluid line. 4.1 Connector will not stay on pump fitting because it is broken. 4.2 Sealing ring in connector missing. 4.3 Sealing ring in connector fitted, but deformed and therefore leaks. 4.4 Damage to washer line by animal. 5. Seal on heating washer fluid reservoir/washer fluid reservoir. Remedy Replace defective component parts only. Do not replace any adjacent component parts that are intact. Note: Repair kits for washer line hoses do exist to allow patches for line damage.
LI82.85-P-0783032024-09-14. Service bulletin. Complaint Individual functions such as sliding sunroof or roller sunblind can no longer be operated using the gesture recognition system. Cause Gesture recognition system control unit software N168 Remedy For vehicles before modification year 23/2: A remedy is currently being developed. Replacing parts will have no effect. For vehicles as of modification year 23/2: Considered to be a series production configuration. A change will not be possible in future.