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Service bulletins for the 2024 Mercedes-Benz CLE

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.

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

By type

By component

By trouble code

Bulletins, newest first
LI33.30-P-0566652025-11-20. Service bulletin. POWER TRAIN. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to micromovement in the connection between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened and must be tightened to the specified torque. Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove outboard side shafts (extract outer joint gearing from wheel hub) 2. Clean contact surface A (see picture file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") using Molykote and leave to dry for one hour in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir or shake it well (for at least 1 minute).
LI68.20-P-0800122025-11-19. Service bulletin. ELECTRICAL SYSTEM. Complaint USB port not functioning properly. Cause Most reported USB port issues are due to improper use or contamination. Note: Any repair costs must be discussed with the customer beforehand. Common external factors identified include: • Fluid intrusion • Broken bushings or physical damage See attachments. Remedy If a component needs replacement but shows no visible external damage, submit a detailed TIPS case only when technical support is required. Include details of all connected external devices (such as charging cables, USB drives, and hard drives). If diagnostic results directly indicate component replacement, a TIPS case is not necessary.
LI68.20-P-0800122025-11-14. Service bulletin. ELECTRICAL SYSTEM. Complaint USB port not functioning properly. Cause Most reported USB port issues are due to improper use or contamination. Note: Any repair costs must be discussed with the customer beforehand. Common external factors identified include: • Fluid intrusion • Broken bushings or physical damage See attachments. Remedy If a component needs replacement without visible external damage, submit a detailed TIPS case. Include information on all connected external devices (e.g., charging cables, USB drives, hard drives).
LI27.60-P-0799692025-11-14. Service bulletin. POWER TRAIN. Complaint Harsh 2-1 downshifts when coming to a stop with ECO start-stop function turned OFF. Note: When ECO start-stop is active, the engine is shut off before the 2-1 shift and the complaint will not occur. Cause Software application when engine is running. Remedy Short-term remedy: Perform IPR and follow the instruction to perform standstill adaptations. Long-term Solution: Aftersales software is currently in development. NOTE: The information contained in this document is intended for use by trained, professional technicians with the knowledge to properly and safely perform diagnosis and repairs on Mercedes-Benz vehicles, using Mercedes-Benz approved tools and equipment. It informs service technicians about conditions that could occur in certain vehicles and provides information that could assist in proper vehicle diagnosis, service, or repair. It does not indicate that a defect is present in any vehicle referenced in this document nor does it imply warranty coverage. DO NOT assume that a symptom or condition, or a described cause of a symptom or condition, affects any particular vehicle or groups of vehicles, or that a described repair applies to any particular vehicle or groups of vehicles. There can be multiple causes resulting in the same or similar symptoms or conditions described in this document, and trained professional service technicians must use their diagnostic skills to make evaluations on a case-by-case basis. The information contained in this document does not guarantee warranty coverage nor does it extend the vehicle’s warranty in any way.
LI27.60-P-0799682025-11-07. Service bulletin. POWER TRAIN. Complaint A harsh 5-4 downshift can be felt during deceleration while braking or coasting. It may be mistaken for a hard brake engagement Cause Poor learning of brake B06 adaptation values over time. Remedy Short-term remedy: 1. Perform IPR and follow the instructions. 2. Perform resetting of deceleration values (VGS > Special Procedures > Special procedure > Resetting learned values Deceleration mode) 3. Perform standard adaptation 4. Reevaluate the concern and release vehicle if no longer present Note: ALL steps (resetting learned values and standard adaptation) must be completed to fully resolve the complaint. Long-term measure: Aftersales software is currently in development.
LI32.25-P-0797072025-10-27. Service bulletin. SUSPENSION. Complaint Wheezing noises/squeaking noises from the front shock absorbers when passing over surface undulations and rough road. Noise MUST match those heard in the attached videos. Cause • Wheezing noises: Flow noises of the damper oil • Squeaking noises: From the mechanical rubber valve in the dividing piston Remedy In case of complaints, the front shock absorbers must be replaced with parts past clean point. • Part clean point is on or after April 2024. • When receiving new parts, check manufacture date (example shown below). • If parts were produced prior to the clean point date, do not install, return. If shocks have been replaced and noise persists, please open a TIPS case to the Body, Chassis, Entertainment inbox.
LI42.10-P-0799042025-10-21. Service bulletin. SERVICE BRAKES. Complaint At low speeds and light brake pressure, brakes will make a groaning or honking noise. Cause Frictional vibrations with very light brake pressure/modulations. Remedy This condition can be duplicated on most vehicles. To validate, use a like for like reference vehicle. The noise is normal behavior under the conditions listed. With very light brake pressure this noise can be induced/caused due to normal brake pad and brake rotor vibrations. Exchanging brake components will not rectify.
LI82.62-P-0786312025-10-14. Service bulletin. ELECTRICAL SYSTEM. Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment. Note: Please refer to this document in the warranty claim and, once diagnosis is completed, select the damage code depending on the component part that is causing the issue. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10-P-067691. Note: In this case, do not use the damage codes for the speakers in the warranty claim.
LI54.10-P-0714992025-09-25. Service bulletin. ELECTRICAL SYSTEM. Complaint The result from the XENTRY battery test does not match the current state of the battery. Cause The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM or EZS cannot record the data if the battery is discharged. Note: A discharged battery does not necessarily need to be replaced. A discharged battery may be recovered with no permanent damage. Remedy 1) If the battery is discharged, charge the battery. Review WS54.00-P-0037B for minimum charger specifications. • Note the amperage difference between trickle (maintainer) chargers of at least 16A and quick chargers of at least 30A. • Review AP54.10-P-5449U. Note when battery is sufficiently charged the charger current is less 5A. 2) While charging the battery, analyze the vehicle data to determine root cause of discharge using the following data points: • NOTE: For guidance on use of the on-board electrical data please review the AKUBIS video titled "New onboard electrical system diagnosis shown on BR 166". The video can be accessed through WIS by following the path WSM--> content by model series --> passenger cars --> ML-Class --> Model 166 --> group 54 --> New onboard electrical system diagnosis. • Refer to the March 2023 PCTT for the video walkthrough of analysis as well as the attachment of the slides to this Li. • Review GF54.10-P-1012A regarding what can cause deep discharge protection to not end a battery draw. • Review SI54.10-P-0024A for proper maintenance of the vehicle. For Star 2 vehicles: -Review FSAM on-board electrical data conspicuous records • NOTE: This data can be found via FSAM N10/6 -> Actual Values -> On-board electrical system -> On-board electrical system data For Star 3 vehicles: -Review N73/3 EZS on-board electrical data conspicuous records • NOTE: This data can be found via EZS N73/3 -> Actual Values -> On-board electrical system -> On-board electrical system data 3) Determine if root cause is due to: • vehicle technical issue? • customer behavior? NOTE: Recommend using battery analysis sheet found in XiW -> Local Contents -> Diagnostic info -> Battery Discharge Worksheet 4) If battery still does not accept charge AND the vehicle does not fall within the parameters of improper maintenance, then create a TIPS case. *IMPORTANT* - If the improper maintenance/use is found during diagnosis, DO NOT open a TIPS case. If a TIPS case is opened, it will be marked 1 star and directed to your assigned FSE for review. TIPS Case must include with the case: • Amperage setting of charger and time battery was on charger • XENTRY Battery Tester results • Voltage of battery taken with multimeter: Do not connect charger while taking measurements • N10/6 FSAM, (N73 or N73/3) and (N73*1 or N73/3*1) • Workshop analysis of conspicuous data • Root cause analysis for battery discharge based on the above documents (technical, customer, etc.) • NOTE: For expedited results when creating a case write customer complaint as "XENTRY Battery Tester implausible".
LI54.71-P-0796722025-09-03. Service bulletin. ELECTRICAL SYSTEM. Complaint Message in Instrument Cluster for "Active Distance Assist not enabled, but can be purchased subsequently" even if Digital Extra: Active Distance Assist DISTRONIC (207) has already been activated/purchased via the application. Cause On some vehicles with Digital Extra: Active Distance Assist DISTRONIC (code 207), it may be that the function cannot be enabled via the application or is no longer available in the "vehicle back end". Remedy Please open a case with the Customer Care Center ("CCC") to reactivate function on the "vehicle back end".
LI46.10-P-0793742025-08-21. Service bulletin. STEERING; SUSPENSION. Complaint Customer concern for ESP/Brake or Steering yellow instrument cluster message AND C220564 in the N80 Steering Column Control Module (Valeo Parts only). To check which supplier steering column module is present in the vehicle, see attachment "Supplier Identification". Cause Triggered due to communication related software timing. Remedy New software A2239026336. Update N80 (Steering Column Module) to target software A2239026336 and perform ignition cycle. Note: If the DTC is present after software update and ignition cycle, please create a TIPS case
OTA - 202506272025-06-27. Over-the-air update. LANE DEPARTURE: ASSIST; LANE DEPARTURE: WARNING; FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL; ELECTRICAL SYSTEM. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has updated driver assistance system SCN coding available for certain subject vehicles. The updated SCN coding improves system stability and enhances the availability of driver assistance features. MBUSA will conduct an OTA service campaign. Remote SCN coding updates are automatically downloaded and installed in the customer’s vehicle free of charge and do not require a dealer visit.
LI33.30-P-0566652025-06-03. Service bulletin. POWER TRAIN. Complaint Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The clunk is heard once when changing from forward to reverse (and vice versa). Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to micromovement in the connection between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened and must be tightened to the specified torque. Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove outboard side shafts (extract outer joint gearing from wheel hub) 2. Clean contact surface A (see image file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") using Molykote and leave to dry for one hour in removed condition 4. Reinstall side shafts
OTA - 050220252025-06-03. Over-the-air update. ELECTRICAL SYSTEM. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the ignition lock (EZS) control unit does not correspond with the latest series production configuration. The EZS control unit will receive an OTA software update which will improve the performance of hands-free access on the affected vehicles. MBUSA will conduct an OTA service campaign. Remote software updates are automatically downloaded and installed in the customer’s vehicle free of charge and do not require a dealer visit.
NCU-20250400132025-05-29. Service campaign. ENGINE. Mercedes-Benz AG, the manufacturer of Mercedes-Benz vehicles, has determined that on certain subject vehicles, the ME-SFI control unit software does not meet current production specifications. As a result, a check engine malfunction indicator lamp might erroneously be triggered.
LI82.10-P-0784702025-05-15. Service bulletin. EXTERIOR LIGHTING. Complaint Message in instrument cluster "Adaptive high beams assistant not available/inoperative" or "DIGITAL LIGHT reduced range of functions" in relation to "FC151E29- The level sensor at front left has a malfunction. There is an invalid signal" in the HLI control unit. Cause HLI control units processing of level sensor data. Remedy Update the software for the HLI control units - starting with the left controller. After the updates, perform SCN coding of the EZS. Please ensure that the SW with the A item number A2239027738 (or newer) is used. Parts replacements will not resolve complaint. Do not replace parts. If concern is not resolved by software, please open a TIPS case and send to the Body/Chassis/Entertainment inbox. Concern does not impact drivability of the vehicle or the function of the headlights.
LI82.10-P-0784702025-05-14. Service bulletin. EXTERIOR LIGHTING. Complaint Message in instrument cluster "Adaptive high beams assistant not available/inoperative" or "DIGITAL LIGHT reduced range of functions" in relation to "FC151E29- The level sensor at front left has a malfunction. There is an invalid signal" in the HLI control unit. Cause HLI control units processing of level sensor data. Remedy Update the software for the HLI control units - starting with the left (driver side) controller. After the updates, perform SCN coding of the EZS. Parts replacements will not resolve complaint. Do not replace parts. If concern is not resolved by software, please open a TIPS case and send to the Body/Chassis/Entertainment inbox. Concern does not impact drivability of the vehicle or the function of the headlights.
LI54.10-P-0714992025-05-09. Service bulletin. ELECTRICAL SYSTEM. Complaint The result from the XENTRY battery test does not match the current state of the battery. Cause The XENTRY battery tester uses the stored on-board electrical system data in the SAM module to access the health of the 12 volt battery. The XENTRY battery test may not take into account a single discharge event because the SAM or EZS cannot record the data if the battery is discharged. Note: A discharged battery does not necessarily need to be replaced. A discharged battery may be recovered with no permanent damage. Remedy 1) If the battery is discharged, charge the battery. Review WS54.00-P-0037B for minimum charger specifications. • Note the amperage difference between trickle (maintainer) chargers of at least 16A and quick chargers of at least 30A. • Review AP54.10-P-5449U. Note when battery is sufficiently charged the charger current is less 5A. 2) While charging the battery, analyze the vehicle data to determine root cause of discharge using the following data points: • NOTE: For guidance on use of the on-board electrical data please review the AKUBIS video titled "New onboard electrical system diagnosis shown on BR 166". The video can be accessed through WIS by following the path WSM--> content by model series --> passenger cars --> ML-Class --> Model 166 --> group 54 --> New onboard electrical system diagnosis. • Refer to the March 2023 PCTT for the video walkthrough of analysis as well as the attachment of the slides to this Li. For Star 2 vehicles: -Review FSAM on-board electrical data conspicuous records • NOTE: This data can be found via FSAM N10/6 -> Actual Values -> On-board electrical system -> On-board electrical system data For Star 3 vehicles: -Review N73/3 EZS on-board electrical data conspicuous records • NOTE: This data can be found via EZS N73/3 -> Actual Values -> On-board electrical system -> On-board electrical system data 3) Determine if root cause is due to: • vehicle technical issue? • customer behavior? NOTE: Recommend using battery analysis sheet found in XiW -> Local Contents -> Diagnostic info -> Battery Discharge Worksheet 4) If battery still does not accept charge, create a TIPS case. -Must include with the case: • Amperage setting of charger and time battery was on charger • XENTRY Battery Tester results • Voltage of battery taken with multimeter: Do not connect charger while taking measurements • N10/6 FSAM and N73/3 EZS CUL • Workshop analysis of conspicuous data • Root cause analysis for battery discharge based on the above documents (technical, customer, etc.) • NOTE: For expedited results when creating a case write customer complaint as "XENTRY Battery Tester implausible".
LI46.10-P-0780122025-05-09. Service bulletin. FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING; LANE DEPARTURE: ASSIST; STEERING. Complaint Hand detection system not operating correctly / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" Cause Possible causes: the hand detection mat, the hand detection control unit, the contacts and the steering wheel harness. Remedy In the event of a customer complaint and fault code in IDC control unit: U186B29 in IDC223 or fault code U0429E0, U042941, U042929, U042902, U0429E1 in IDC213 or fault code in HOSWD control unit: B1E7614 Test: Please perform the new SCN coding for HOSWD control unit (N179/1) (available since May 2025). Please flash the IDC (N62/4) software A223 902 75 37 (only applies to HOSWD223). Erase fault memory Remedy: Switch on ignition without touching the steering wheel. If after 10 seconds without touching the steering wheel, one of the two fault messages appears in the IC: Please check contacts and feed lines in the steering wheel by means of visual inspection for damage, crimped connections, loose connections, etc. (example in picture 2 and 3). If there is visible damage -> replace steering wheel electronics or feed lines. If there is no visible damage -> Please create TIPS case! If no yellow message appears in the instrument cluster within 10 seconds: Please grab the steering wheel all the way round, including the 6 o'clock chrome molding, with both hands (see picture 1). If the fault is triggered by grabbing the steering wheel rim or pressing on the 6 o'clock clasp, check contacts and feed lines in the steering wheel by means of visual inspection for damage, crimped connections, loose connections, etc. (example in picture 2 and 3). Check ground connections (screw connections and cable to steering wheel rim); if necessary tighten screws/bolts and check for corrosion (Picture 4). If there is visible damage -> replace steering wheel electronics or feed lines. If no fault is visible: Please open a TIPS case! In the event of a customer complaint and further fault code in HOSWD: B1E7713: Check ground connections (screw connections and cable to steering wheel rim); if necessary tighten screws/bolts and check for corrosion (Picture 4). B1F1F04: Check hand detection system control unit; if necessary swap with donor vehicle (ensure that the HW part numbers are identical).
LI82.85-P-0773162025-05-06. Service bulletin. ELECTRICAL SYSTEM. Complaint Symptoms relating to CIVIC A26/17 - MBUX multimedia system + instrument cluster (head unit)] and/or displays Cause Enhanced technical support process for CIVIC modules and associated displays Remedy Note: Do not replace any components. For all symptoms concerning CIVIC and displays create a TIPS case after performing initial diagnosis. Attach the following documents to this case: • Quick test • Control unit logs for CIVIC and all displays • If possible, obtain customer consent for CIVIC logging that needs to be reviewed by GSP (see attachment). In some instances the CIVIC logs may not be required. After receiving the case if it is determined that CIVIC logging is required, a password will be generated for activation of the CIVIC logging (where the customer has approved this). This password and Xentry instruction on how to create a log will be communicated in the TIPS case. The password is case sensitive and only valid for 24 hours. Note: If unable to obtain the customer approval for CIVIC logging, simply state so in the TIPS case notes.
LI82.60-P-0791382025-05-06. Service bulletin. ELECTRICAL SYSTEM. Complaint In vehicles with the MBUX multimedia system Gen20x.i2 without premium sound system and external amplifier, the sound does not meet the customer's expectations. Changing the sound settings, for example for the bass, does not provide the desired effect. Cause Sound parameter software in the A26/17 - MBUX multimedia system + Instrument cluster (Head unit) control unit Remedy For vehicles with standard sound and Midline sound system (code 853), new sound parameters are available. V/X 254: A 254 903 94 03 C 254: A 254 903 97 03 V/W 206: A 206 903 20 04 S 206: A 206 903 21 04 A/C 236: A 236 903 86 01 V/W 214: A 214 903 19 03 S 214: A 214 903 20 03 To update the sound parameters, please perform an update to the software for the A26/17 - MBUX multimedia system + Instrument cluster (Head unit) control unit.
LI46.10-P-0780122025-05-02. Service bulletin. STEERING; ELECTRICAL SYSTEM. Complaint Hand detection system not operating correctly / vehicles with code 266 Fault message in instrument cluster: "Active Emergency Stop Assist not available" "Active Lane Keeping Assist not available" Cause Possible causes: the hand detection mat, the hand detection control unit, the contacts and the steering wheel harness. Remedy Test Procedure: Perform an initial quick test with freeze frame data. Save the N179 - Hand detection system (HE) and N62/4 - Driver assistance system (SG-FAS) control unit logs. Note the fault frequency of fault codes set. Delete the N179 and N62/4 fault memory. Test: Please flash the IDC (N62/4) software A223 902 75 37 (only applies to HOSWD223). Erase fault memory Reset the HOSWD control unit in line with the guided test in Xentry. Using both hands, "scan" the steering wheel all the way round, including the chrome molding at 6 o'clock (see Picture 1). Read out fault memory and follow steps below for any faults set. Remedy: Switch on ignition without touching the steering wheel. If after 10 seconds without touching the steering wheel, one of the two fault messages appears in the IC: Please check contacts and feed lines in the steering wheel by means of visual inspection for damage, crimped connections, loose connections, etc. (example in picture 2 and 3). If there is visible damage -> replace steering wheel electronics or feed lines. If there is no visible damage -> replace steering wheel rim. If no yellow message appears in the instrument cluster within 10 seconds: Please grab the steering wheel all the way round, including the 6 o'clock chrome molding, with both hands (see picture 1). If the fault is triggered by grabbing the steering wheel rim or pressing on the 6 o'clock clasp, check contacts and feed lines in the steering wheel by means of visual inspection for damage, crimped connections, loose connections, etc. (example in picture 2 and 3). Check ground connections (screw connections and cable to steering wheel rim); if necessary tighten screws/bolts and check for corrosion (Picture 4). If there is visible damage -> replace steering wheel electronics or feed lines. If no defect is visible: Please do not replace the steering wheel, but wait for new coding parameters which should be available 05/2025. Vehicles with control unit N179 - Hand detection system (HE): B1E7614: Check contacts and wiring harness in steering wheel by carrying out a visual check for damage, pinched areas, loose connections, etc. (examples in Figs. 2 and 3); If no damage is noted replace the N135 - Steering wheel electronics (LRE) and reassess. If fault code returns replace the steering wheel. B1E7713: Please check the wires and connections in the steering wheel. Afterwards, please check whether the complaint is caused by over torqued screws on steering wheel trim pieces. To do this, please loosen the screws slightly and reevaluate the situation. (Picture 4). P164456: Perform SCN coding. P1CA000: Perform an initial start-up on the N179 hand detection control unit. Faults in N62/4 - Driver assistance system (SG-FAS) control unit with U186B29, U0429E0, U042941, U042929, U042902, U0429E1: If no fault is stored in the N179 control unit: Scan steering wheel as indicated in the test procedure and check whether the fault is reproducible. If no fault code is stored in the hand detection control unit, the fault codes in the driver assistance systems control unit are precautionary messages. Software for the N62/4 - Driver assistance system (SG-FAS) is now available for Star 3 vehicles only. Fault in IDC223 control unit: U186B29: Delete fault memory and flash the new IDC (N62/4) software A223 902 75 37. If the software update is not available, or the problem persists, create a TIPS case. Fault in IDC213 control unit: U0429E0, U042941, U042929, U042902, U0429E1: If no fault is stored in the HOSWD control unit then scan the steering wheel and check whether the fault is reproducible. If reproducible: Create a TIPS case, adding the
LI82.10-P-0788962025-05-02. Service bulletin. EXTERIOR LIGHTING. Complaint Headlamps leaking or fogged Cause The fogging of the headlamp is a natural phenomenon which can occur under certain climatic conditions. In contrast to a leaky headlamp, physical fogging does not result in a technical impairment of the headlamp. A leak test must be performed to determine if physical fogging exists or if the headlamp is leaky. Remedy Check for external damage: You can identify a damaged headlamp in the following way: For headlamps with a closed system 1. Check the headlamps for any external damage and check also for correct seating of the Gore-diaphragm/correct latching of the cover caps. 2. If the headlamp exhibits any external damage, replace the headlamp. For headlamps with an open system 1. Check the headlamps for any external damage and seal off the vent, then make sure the cover caps are latched correctly into place. 2. If the headlamp exhibits any external damage, replace the headlamp. Note: External damage to the headlamp does not present a warranty or goodwill case. 1. Clear fogged/condensed LED headlamps and LED rear lamps: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the hood or trunk. 4. Switch on the lights. 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 (thawing progress). 7. If the condensation has disappeared, nothing else has to be done. Note: If defrosting has been performed, you can skip the first step. 2. Leak test of headlamp with overpressure: • Connect test adapter to pressure tester. (Figure 1) • Check test adapter for leak tightness. To do so, connect plug and coupling (picture 2) and apply a maximum overpressure of 30 mbar. The pressure must remain constant. If the pressure does not remain constant, use a new adapter. • All vents have to be sealed with sealing compound and the existing diaphragm with the stamp (picture 3 [3]). (Picture 4) Make allowance for the different headlamp variants here (there are different outlet openings). • Check if the headlamp needs to be removed to gain access to the diagnostic socket on the headlamp housing. • Plug the adapter onto the diagnostic socket on the headlamp housing. (Picture 5). • Apply a maximum of 30 mbar overpressure to the headlamp housing. Note: If the maximum overpressure of 50 mbar is exceeded the headlamp seal will be damaged (picture 6). • If a pressure drop of less than 10 mbar is measured within 30 seconds, the headlamp is tight and there is natural physical condensation. • If a higher pressure drop than 10 mbar is measured within 30 seconds, the headlamp is leaky. Note: The leaky position can be localized with the aid of soap suds. If the pressure test is not passed, the headlamp is leaky. If the cause cannot be rectified, the headlamp must be replaced. Note: If the headlamp is replaced, no dry packs may be installed on the new replacement headlamp. AR82.10-P-5455WT was created for the pressure test. This AR can be used as a reference manual for all closed headlamps. In the event of an open headlamp system, the vent ducts must be sealed before the pressure test.
LI82.10-P-0783012025-05-02. Service bulletin. EXTERIOR LIGHTING. Complaint Headlamp, front fog lamp leaky or fogged Cause Fogging of the headlamps is a natural phenomenon, which can occur under certain climatic conditions. It does not lead to any technical impairment of the headlamp. Remedy NOTE: If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps and LED rear lamps: 1. Drive vehicle into workshop (temperature higher than +18 °C/+64.4 °F) and connect the exhaust extraction. Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the hood or trunk. 4. Switch on the lights. 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 (thawing progress). Clearing fogged/condensed halogen/xenon headlamps: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine. 3. Open the hood. 4. Switch off the lights. 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 (thawing progress). Note: If there is no visible reduction in the formation of condensation, check the headlamp for damage. (See Remedy 2) It is not physically possible to defog the headlamps completely. Fogging does not impair the operation or the service life of the headlamp. Remedy 2 A damaged headlamp can be identified as follows: 1. Check the headlamp for external damage and that the cover caps and the diaphragm are correctly seated. 2. Check the electrical connectors of the plugs and pins. 3. Check for leak tightness in accordance with LI82.10-P-078896 The test can only be conducted on headlamps. 4. If the headlamp or the rear lamp has any external damage, replace the component part in accordance with the WIS instructions.
LI83.30-P-0790812025-04-24. Service bulletin. VISIBILITY/WIPER. Complaint Random heating of air conditioning system. Cause Temperature sensor in overhead control panel (OCP) delivering incorrect values: The temperature sensor in the overhead control panel is malfunctioning. Fault code B110709 or fault code B11F697 are present in the overhead control panel with the status (active) or (active stored). or The temperature sensor in the overhead control panel measures an incorrect temperature (the temperature value can be checked against the actual value in the overhead control panel) If the above-mentioned fault code is not present, the cause could be malfunction on the air conditioning system. Remedy If one of the above-mentioned fault codes should occur, a TIPS case must be created here. If the above fault codes or actual value differences are present in the OCP - please send the case to the Body/Chassis/ Entertainment inbox. Otherwise, the case must be sent to the HV/LV inbox for support in A/C diagnosis. *** It is not necessary to replace the overhead control panel ***

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