Technical service bulletins are instructions a manufacturer sent its dealers about a known fault. They are not recalls and the work is usually not free, but they are the clearest signal of a problem the manufacturer already knows about.
LI46.00-P-079786
Service Bulletin/Repair Instructions
Complaint Noise from front end thought to be from steering gear. Cause During diagnostics of a front end noise, workshop is under the impression the noise is coming from the steering gear. Remedy If the root cause of the noise cannot be found and is seemingly from the steering rack, perform the below LI's and diagnostics. If they have been performed and the root cause still cannot be determined, a TIPS case must be opened to the Body/Chassis/Entertainment team prior to replacing the steering rack. • LI46.35‑P‑067339 ‑ "Rattling, Humming, Dry Sliding/Gravel Noise When Steering" • LI46.35‑P‑071461 ‑ "Check Tie Rod Outer Joint of Steering Gear" • LI46.10‑P‑077391 ‑ "Knocking Noise In The Area Of The Steering Gear or Steering Column Tube When Braking Or Moving Off; The Steering Wheel Can Also Be Felt To "Crack"" • Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Keep the boot clamps in case the rack is returned. • If the noise is described as "clacking" or "knocking" when moving the wheel back and forth in quick oscillations and the thrust element in the steering rack has NOT been checked yet, please perform a check and subsequent adjustment, if necessary, as detailed in AR46.20‑P‑0601ME. • Remove sway bar links and see if noise persists. • Perform NVH time‑domain noise diagnosis pointing to the steering rack as the root cause. The TIPS case must contain the following: • Video underneath the vehicle with clearly audible noise while engine is running. • Video inside the vehicle with clearly audible noise while engine is running. • Vehicle checked for history of collisions. • Vehicle history checked for other noise complaints in the area. • List of other checked components (suspension, drive line components, wheel bearings, etc...). • Along with the audible noise, does the feel/noise change through only a certain part of the steering arc sweep? • Provide the thrust element before and after readings.
LI46.35-P-067339
Service Bulletin/Repair Instructions
Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or control the vehicle. Cause Ball screw drive (KGT) of electric steering damaged by: 1. External force due to: ‑ Hitting the curb/posts with the front wheels. ‑ Driving over obstacles (e.g. pothole/ threshold/ speed bump/ gully) at an inappropriate speed. 2. Corrosion/ water ingress through a damaged boot (see attachment). ‑ Cracks (1) ‑ High pressure cleaner (2) ‑ Animal bite (3) See various examples listed in the attachments for examples of outside influence. Remedy Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Replace electric steering. Note: Steering gears replaced due to outside influence or damage must not be claimed under warranty!
LI72.20-P-075746
Service Bulletin/Repair Instructions
Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket, handbag etc. Remedy As of the 6th generation, the vehicle key can be recoded so that the tailgate no longer opens as a result of a long press on the button, but by double‑clicking on the button instead. This reduces the likelihood of the button being activated accidentally or unintentionally. The recoding can be carried out as follows: 1. Add SA Code O19 into VeDoc (O for Oscar, not "zero") • an XSS ticket may be necessary to add the SA code 2. Perform SCN coding of EIS N73 control unit 3. Deactivate the vehicle key (a successful deactivation is indicated by the LED lighting up 2x briefly and then 1x for a long period). 4. Place the vehicle key in the storage compartment on the key symbol and turn on the ignition. IMPORTANT: all other vehicle keys must be outside the recognition range of the vehicle when doing this! Perform steps 3 and 4 successively for all vehicle keys. Notes: 6th, 7th and 8th generation keys can be deactivated as follows: Up to modification year 22/1 by double clicking the "Lock button" As of modification year 22/1, by press and holding the “Lock button", then double‑click the “Unlock button" at the same time. On model series 167, the storage compartment with the key symbol is located in the armrest. The SCN coding from the EZS is only transferred correctly to the vehicle key under the following conditions: Only one vehicle key is located in the vehicle, this key has been deactivated and it is positioned on the marking in the storage compartment for the data transfer. The costs for this adaptation are to be borne by the customer. For the newer BR 174, 178, 244, 248, 520, and 540, a software update must be initiated, as there is no way to perform SCN coding.
LI54.71-P-079104
Service Bulletin/Repair Instructions
Complaint Traffic sign symbol for "Traffic Sign Assist" is blinking in instrument cluster without obvious cause usually with one of the following scenarios: • Flashing without a speed limit ("‑ ‑"). • Flashing when current vehicle speed is under speed limit. • Flashing between US speed limit symbol and European speed limit symbol. NOTE: • Verify that the concern falls under one of the attachment videos. If not, then it is outside of the scope of this LI. • This also does not cover "Traffic Sign Inoperative" messages on the instrument cluster. Cause There are two identified reasons for this concern: 1. Country code information stored incorrectly at a particular geographic latitude range. 2. Incorrect reference data when the vehicle is started and a GPS signal is not immediately available. Remedy Update head unit software to latest version and the re‑check function in the same location. If vehicle is still exhibiting one of the symptoms as described exactly as in the complaint section or as shown in the video attachments, open a TIPS case to the Body/Chassis/Entertainment inbox with the following: • Video of the concern. • Exact location (latitude and longitude is best)
LI54.65-P-080132
Service Bulletin/Repair Instructions
Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5. Cameras 6. Other Park Topics. Cause Various root causes Remedy See attached diagnostic guide.
LI82.62-P-078631
Service Bulletin/Repair Instructions
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. Information: Please refer to this document in the warranty claim and, after completing diagnosis, select the damage code corresponding to the component part that caused the problem. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10-P-067691. Information: In this case, do not use a damage code for the speakers in the warranty claim!
LI54.21-P-080326
Service Bulletin/Repair Instructions
Complaint CEL light on with no drivability concerns. Cause Signal timing error. Remedy 167, 465: SW has been released. Update the FSAM to the latest SW version. 290, 118, 243, 247: Software is still in development. This fault code does not cause a drivability concern and will clear itself within 2-3 key cycles. The vehicle can be released back to the customer.
LI35.30-P-058566
Service Bulletin/Repair Instructions
Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The noise is heard once in each instance when changing direction of travel. 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 cracking of the microweld 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. See also LI33.20-P-078406 Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove side shafts 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") with Molykote and leave to dry for "one hour" in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir it or shake it thoroughly for (at least 1 minute).
LI82.60-P-080383
Service Bulletin/Repair Instructions
Complaint Radio station cover art does not refresh when switching stations. The UI continues to show the old station’s artwork instead of updating to the new one. Cause When a new station change request is triggered, a temporary glitch is causing the Head Unit application to fail to overwrite the previous request. This glitch is causing the cover art mismatch in the Radio application. Remedy Please do not replace any parts. The E505.9 software is released and available in XENTRY Q3 2026.
PSL-NCU Return Parts 7/3
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 23rd, 2026. After July 23rd, 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.
LI82.60-P-080702
Service Bulletin/Repair Instructions
Complaint 1. Maybach Night Series image not being displayed in Head Unit, Instrument Cluster, CCR and RSU displays 2. Car line picture mismatch between Instrument Cluster and Head Unit display 3. Menu icons missing in Head Unit, Instrument Cluster, CCR and RSU displays Cause Incorrect variant coding of SCN Remedy Please do not replace any parts Perform SCN coding of HU7, IC, CCRAD and RSU7 control units.
LI00.20-P-077615
Service Bulletin/Repair Instructions
Complaint 1. "Perform vehicle handover" in the workshop menu to start the maintenance computer for service A/B cannot be carried out. 2. Service confirmation is not possible because "Perform vehicle handover" is displayed. This cannot be carried out. 3. The service display in the instrument cluster permanently displays 365 days (remaining time) and does not change. Cause Routine change in the software in N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)). Vehicle handover was not performed. Remedy For model series 290 AMG up to and including AEJ 22 and model series 167 up to and including AEJ 21/2, the following applies: Manually commission already-installed instrument cluster control unit N133/1 and then perform special procedure to re-initialize ASSYST data in N127 powertrain control unit. For model series 167 as of AEJ 22/1, 192 AMG, 206, 214, 232 AMG, 236, 254, 290 AMG as of AEJ 23, 294, 295, 296, 297 and 465, the following applies: Reinitialize ASSYST Plus under Adaptations – Teach-in processes – ASSYST PLUS in control unit N133/1 (instrument cluster) or A26/17 (MBUX multimedia system and instrument cluster (head unit)), and then perform the special procedure for reinitializing the ASSYST data in powertrain control unit N127.
LI00.20-P-080703
Service Bulletin/Repair Instructions
Complaint Service code B1 displayed in the customer menu does not match the workshop code displayed in the workshop menu, e.g., 505 or 550A, which includes a service A. Cause The root cause is currently being investigated. Remedy To determine the cause, the instrument cluster control unit (N133/1) and powertrain control unit (N127) logs are required before confirming the service or correction using XENTRY Diagnosis. Please open a TIPS case to BCE inbox with the requested information in the attachments.
LI32.34-P-080645
Service Bulletin/Repair Instructions
Complaint Rattle or clunking noise from underneath the vehicle when driving over uneven/bumpy surfaces. Cause Internal tolerances of the electric rollbar. Remedy 1. Confirm front or rear roll bar. 2. Remove the affected sway bar links and carefully drive vehicle. • Noise not resolved with sway bar links removed > Not appliable to this LI, noise is from a different component. • Noise resolved with sway bar links removed > Current parts may make some noise and is currently state of the art. Optimized, quieter parts will be available Q4 2026, please release vehicle until such time parts are available. For further questions, inquiries, or sound levels approximately equal to or above what is shown in the attachment, open a TIPS case to the Body, Chassis, Entertainment inbox.
PSL-NCU Return Parts 5/29
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, June 18, 2026. After June 18th, 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.
LI82.85-P-080507
Service Bulletin/Repair Instructions
Complaint After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the message "SOS - service not activated" appears on the instrument cluster. In addition, the following two conditions are also met: • HERMES (N112/9) control unit: event code B15CE00 is ACTIVE and STORED (A+S) • Vehicle Documentation System: For the HERMES control unit, the EID1, EID2, ICCID, IMEI, IMSI, TELNR fields in the "Identification/Serial number" column have the value "-" Cause Still under analysis Remedy Recommission the HERMES control unit (N112/9) with XENTRY Diagnosis 03/2026 and add-on 33399 installed or carry out the procedure with a newer version of XENTRY Diagnosis: XENTRY→ "N112/9 - Control unit for telematics services (HERMES)" -> "Adaptations" -> "Control unit commissioning" -> "Commissioning of previously installed control unit"
LI46.15-P-070510
Service Bulletin/Repair Instructions
Complaint Noises from the area of the steering column. - Creaking - Squeaking - Chattering - Humming - Grinding Cause At present, there are no known noise problems with the steering column. Remedy Check surrounding area of the steering column for possible noises. • Instrument panel support • Steering column switch module NOTE: Occasionally to verify complaint, the steering column/vehicle needs to be in direct sunlight or hot conditions for a few hours. If noise only occurs when adjusting the steering column via electric actuation, please perform: 1. Disassemble bellows of steering column tube module. 2. Move steering column entirely out and entirely down. 3. Grease steering column on all pivot points including, but not limited to, green-marked positions with a suitable brush (find pictures in attachment). 4. Move column up 1/4 of the way and grease again. 5. Continue until upper limit stop is reached. 6. Then move steering column adjustment in all directions from limit stop to limit stop several times to work in the grease. 7. If noise does not resolve, wipe excess grease off and perform greasing and movement to limit stops in all directions again. For all other noises or if the above does not resolve, create a TIPS case Body, Chassis, and Entertainment inbox. Attach a detailed description of the noise complaint, images, and a recording of the noise. Include detailed items of the following: • Position of height and longitudinal adjustment when the noise occurs • If possible, locate affected component part on steering column • State any change in the noise when steering column component parts are touched (e.g. spring, etc.)
LI82.30-P-078932
Service Bulletin/Repair Instructions
Complaint Approx. A 5–10 cm wide unwiped strip remains in the area of the wiper blade attachment during the downward movement of the wiper on the driver's side or front passenger side (see Figure 1). Cause During replacement of worn wiper blades, the wrong blades were installed, contrary to the specifications. Left-hand drive vehicle: Incorrect: A1678209201 Correct: A1678208703 The standard wiper system from model series 167 was changed in October 2022. The wiper arms of the standard system after the switchover have a higher clamping force and are not compatible with the wiper blades before the switchover. The wiper lip of a wiper blade before switchover is deformed due to the higher contact pressure of the wiper arm, which can result in a 5–10 cm wide strip in the area of the wiper blade attachment not being fully wiped. Identification of the wiper blades installed on the vehicle: Wiper blades for vehicles up to October 2022 have a clip between the connector and the end of the blade Wiper blades for vehicles produced from October 2022 onwards do not have a clip between the connector and the tip of the blade See Picture 2 Note: The correct wiper blades were installed on the vehicle at the factory. This does not constitute a defect attributable to the manufacturer. Remedy Install the correct wiper blades intended for the vehicle
LI82.10-P-080467
Service Bulletin/Repair Instructions
Complaint Despite the IC message shown in these complaints, the primary low-beam function is not restricted. Complaint No. 1: Sporadic "Headlamp Inoperative" message in the instrument cluster (IC), fault code in control unit N10/6 FSAM: • U118A02 communication with the left headlamp range adjustment control unit is faulty. General signal fault. or • U118A08 Communication with the left headlamp range adjustment control unit is faulty. Faulty signal or faulty message. Complaint No. 2: The instrument cluster (IC) displays the message "Adaptive High Beam Assist inoperative"; fault code present in LED control unit E1n11 or E2n11: • B178392 "LED driving light actuation" control unit is faulty. Function or command is faulty. Cause Complaint No. 1: software fault. Complaint No. 2: undervoltage threshold value set inappropriately during vehicle start. Remedy For complaint No. 1 and No. 2: Perform a software update on all headlamp and LED control units: E1n9, E1n11, E2n9 and E2n11 If the fault persists: • For complaint No. 1: Replace HLI E1n9 control unit. • For complaint No. 2: Replace PXL E1n11 or E2n11 control unit. Note: Headlamps must not be replaced for these complaints.
LI33.20-P-078406
Service Bulletin/Repair Instructions
Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle. See also: LI35.30-P-058566 (Throttle Lift-Off Noise - Rear) LI33.30-P-056665 (Throttle Lift-Off Noise - Front) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease) (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced.
PSL-NCU Return Parts 5/08
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, May 28, 2026. After May 28th, 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.
LI54.30-P-080421
Service Bulletin/Repair Instructions
Complaint Head-up display flickering in BR167. Cause Software A 40/12 - Head-up display and N133/1 - Instrument cluster (IC). Remedy Please do not replace any parts The following steps need to be performed in the order shown below: 1. Xentry > Special functions > 'Entry for retrofits and modifications' add SA code 2O8 (Two 'O' eight) (Please see the attachment) 2. Update the HUD177 software update to the latest available version 3. Update the IC177M software update to the latest available version (software A1779048302 )
LI42.10-P-080253
Service Bulletin/Repair Instructions
Complaint When coming to a stop or at slow speeds, brakes produce light squealing noise. Cause Optimized brake pads may produce some noise. Remedy NOTE: Exchanging brake discs for noise is not a permanent measure for noise mitigation and cannot be claimed under warranty according to this LI. If the brake pads have not been exchanged prior and this is the first visit: • Wipe down brake disc and remove any brake dust from holes in brake disc. • Replace brake pads and spring clips. Ensure the double sided adhesive is applied to all locations where the pistons contact the brake pad backing plate. See attachment "Adhesive and Copper Paste Application Area - Series 167". • Apply Molykote to the sides of the brake pad backing plate in the location shown in the attachment "Adhesive and Copper Paste Application Area - Series 167". • Clean brake components thoroughly from brake dust, road debris, and other foreign material. • After replacing, place the vehicle in sport or sport plus mode and engage brake pedal for 30 seconds. • Bed brakes during quality checking according to LI42.10-P-063502 but only perform once. If the brake pads have been exchanged in a prior visit: The following portion is not warrantable, some brake noise, especially with sport brake packages, is normal. The below is intended to assist in reducing or mitigating brake noise for customer satisfaction purposes. • Inspect the condition of the brake system per WIS. • Some level of noise is acceptable and cannot be mitigated or removed at all times. Below is a list of items that can cause or exacerbate noises but are normal. • With use there will be dirt, debris, brake dust, and other foreign contaminants. If the system is dirty, components should be thoroughly cleaned and wiped down. • Inspect the condition of the brake pads and discs. Note any visual anomalies such as glazing, excess rust formation, pad imprints from long stationary times, etc... • Driving styles. Does the noise only occur at very low speeds when coming to a stop such as with very light brake pressure? When coming to a stop and applying increased brake pressure, does the noise reduce or disappear? If so, this is normal operation. • Brake pressure and application style (stop-and-go traffic with consistent low brake pressure “riding brakes” where the brakes cannot cool sufficiently between applications). • Ambient temperatures, especially colder ambient temperatures. Lower ambient temperatures can also introduce additional road debris, such as salt.
LI00.01-P-078887
Service Bulletin/Repair Instructions
Complaint The intent of this document is to provide workshops with helpful technical reference language. • Commonly used acronyms in LI's and TIPS cases. • Control unit names, numbers, and how to identify. • Network/wiring architecture groups to baumuster quick reference. • Platform to baumuster quick reference. Cause Information only Remedy Acronyms: • AV = Actual Values • CPR = Car Package Release (For MB.OS) • CU = Control Unit • CUL = Control Unit Log • DTC = Diagnostic Trouble Code • E-Stand = Fresh-up head unit boot software (found in head unit control unit log) • FUP = Fresh-up • FW = Firmware • HSVL = High Speed Video Line • HU = Head Unit • HW = Hardware • IPD = Injector Performance Data • ISU = Initial Start Up • LVDS = Low Voltage Differential Signal • NAG"x" = New Automatic Gearbox ("x" is the generation number, example: NAG3) • NSFT = Not Safe For Transport • MOPF = Model Facelift (Ex: 167 MOPF) • PiH = Plug-in Hybrid • SA Code = Sonderausstattungscode (Option Code) • SCN = Software Calibration Number • SW = Software • TCU = Telecommunication Control Unit (Hermes/Ramses/Etc...) • QT = Quicktest • XD = XENTRY Diagnosis Control Unit Identification: Refer to the attachment "Control Unit Nomenclature" for location of each. • Control Unit Name • Control Unit Number • Control Unit Short name • Control Unit Diogenes ("dy-oj-uh-neez") name - Control unit variant/family. Network/Wiring Architecture to Baumuster Quick Reference: Star 1 • 117, 156, 246 (MFA) • 166, 176, 221, 242, 246, 292 • 906 Star 2 • 205, 213, 238, 253, 257, 290 (MRA) • 117, 156, 246 (MFA) • 118, 177, 243, 247 (MFA2) • 167, 222, 292, 463, 465 • 907 Star 3 • 294, 295, 296, 297 (EVA2) • 206, 214, 223, 236, 254 (MRA2) • 192 and 232 (MSA) Star 3.5 • 174 • 178 Platform to Baumuster Quick Reference: MRA = "Mercedes-Benz Rearwheel Architecture": • 205 • 213 • 222 • 238 • 253 • 257 • 290 MRA2 = "Mercedes-Benz Rearwheel Architecture - Generation 2": • 206 • 214 • 223 • 236 • 254 MFA = "Mercedes-Benz Frontwheel Architecture" • 117 • 156 • 246 MFA2 = "Mercedes-Benz Frontwheel Architecture - Generation 2" • 118 • 177 • 243 • 247 EVA1.5 = "Electric Vehicle Architecture" • 243 EVA2 = "Electric Vehicle Architecture - Generation 2" • 294 • 295 • 296 • 297 MSA = "Mercedes-Benz Sport Architecture" • 192 • 232 MMA = "Mercedes-Benz Modular Architecture" • 174 • 178
LI88.70-P-079818
Service Bulletin/Repair Instructions
Complaint There may be a cosmetic fault in the projection of the logo projector of the outside mirror (left/right). Cause Delamination of film on carrier plate. Remedy Additional replacement part numbers have been approved for the affected model series V/C/X167, X294 and X296.
LI82.10-P-078301
Service Bulletin/Repair Instructions
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. If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Remedy Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps: 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. 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 of fogged/condensed LED headlamps and LED rear lamps on electric vehicles: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). 2. Connect battery backup via a charger. 3. Open the front-end flap and ensure sufficient ventilation. 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 condensation, check the headlamp for malfunctions. (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. Note: Only implement Remedy 1 for model series 463 (from model year 2018) and model series 465. Remedy 2 A defective 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 according to LI82.10-P-078307. 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. Note: External damage to the headlamp/rear lamp or faulty seating of the cover caps does not present a warranty or goodwill case. Note: With headlamps, it is possible to install desiccant packs if the problem occurs repeatedly. • Open ventilation system LI82.10-P-078302 • Closed ventilation system LI82.10-P-078304