The contact owns a 2010 Mercedes-Benz ML450. The contact stated while driving at an undisclosed speed, after a while, the driver's side seat belt started to retract and eventually became uncomfortably tight. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 150,000.

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).

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

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.

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.

Complaint Vehicle with atypical reduced heat output. Cause Silicate granulate may have escaped from a damaged bag in the expansion reservoir (not visible), reducing the coolant flow in the heater heat exchanger (see picture). Remedy With the aforementioned complaint, make sure that the cooling circuit is inspected for silicate residues after all standard tests are completed. The silicate residues tend to accumulate upstream of the shutoff valve for the heater hot water pulsed valve. If there are silicate residues in the coolant, the engine must be flushed thoroughly. To make sure that all silicate residues are removed from the cooling circuit, the following parts must also be replaced (cleaning of these components is not sufficient): Coolant expansion reservoir, radiator, oil/water heat exchanger (oil cooler), heater valve, heat exchanger of heater, coolant and, if installed, the electric water pump for the residual heat utilization system. Determine the parts for the respective vehicle in the EPC.

Complaint During a phone call, the called party has difficulty understanding/cannot understand the driver, or interference/background noises are audible to the called party during a call. It becomes increasingly difficult to understand as the speed rises. Cause A. Seating of the microphones in the headliner. Side edges are covered by the textile cover (see picture 1) B. Assembly of microphones (B25/20 or B25/21) in the headliner. C. Dirt inside the microphone housing Remedy 1. Press finger on rear of microphone (on adhesive tape) 2. Remove microphone cap from the front 3. Eliminate protruding material residues of the microphone cutout at the headliner, e.g. with a soldering iron. The microphone must be seated in the headliner as shown in picture 2. 4. Push microphone from behind until it is firmly pressed into the headliner 5. Maintain pressure and press/clip cap into microphone from the front. Note: The cover cap must be clearly heard and felt to engage. 6. This procedure must be carried out on both microphones (B25/20 and B25/21) Note: • It is recommended to replace the cover caps. • The non-woven cloth in the cover cap protects the microphone from soiling and must not be removed. 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.

Complaint 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).

Complaint Windows of the front doors poorly adjusted/sluggish Cause The settings of the front windows may be set incorrectly Remedy Adjustment of the windows or window guides as specified in AR72.10-P-1960GQS . A video with further information on instructions can be found in the attachment. Description of the videos: Safety Information: 1. AS00.00-Z-0011-01A Risk of injury with trapped or crushed fingers when performing removal/installation and adjustment work on hoods, doors, lids and sliding roof 2. AH67.00-P-0003-01FB Notes on avoiding damage to glass and windows of special protection vehicles Work Procedures: 1. Connect the operating switch to the door wiring harness and partially raise the window (not illustrated) 2. Slacken and remove the upper nuts on both spacers 3. Carefully lift the window off the spacer and move it towards the rear against the rear window guide 4. Lower the window again and check the offset between the spacer and the mounting holes at the rear and front 5. Adjust the mounting at the rear - The window must lie parallel against the rear guide along its entire length - Undo the fasteners of the bracket on the window lifter - Align the bracket with spacer to the bore in the window mounting, first in the longitudinal direction and then vertically - Tighten the fasteners of the bracket/window lifter (M6) 12 + 5 Nm - Fit the nut on the spacer at the top but do not tighten it 6. Adjust the mounting at the front - Lift the window; it must lie parallel against the rear guide along its entire length - Undo the fasteners for fore/aft adjustment - Align the bracket with spacer to the bore in the window mounting, first in the longitudinal direction and then vertically - Tighten the fasteners of the bracket/window lifter (M6) 12 + 5 Nm. Fit the nut on the spacer at the top and tighten it (M6) 12 + 5 Nm 7. Now tighten the nut on the rear spacer at the top (M6) 12 + 5 Nm 8. Check the movement of the window - On the outside of the window, mark the position of the window relative to the rear window guide with tape - Open and close the window several times - The movement of the window should run parallel and uniformly along the guide, free of any tilting motion - Repeat the adjustment procedure if necessary 9. To complete the adjustment, check the window for ease of movement. To do this, measure the power consumption of the window lifter motor. The maximum current draw is approximately 9 Amps while the window is being raised.

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). 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 Note: Before using the antifriction coating (Molykote), stir it or shake it thoroughly for (at least 1 minute).

Complaint Transmission control unit Y3/8n4 (fully integrated transmission control unit (VGS)) not listed in quick test and/or no communication possible with VGS. Cause Transmission control unit Y3/8n4 Remedy It is important that LI54.15-P-057373 is processed before replacing any component parts (transmission 722.9). After processing and complying with the above documents, perform a reset on the transmission control unit Y3/8n4 (VGS) (ignition reset), check that the transmission connector is seated correctly and inspect the PINs for concerns. If communication with the VGS cannot be established afterwards, the component part 'electrohydraulic controller unit (EHS)' must be replaced, as it is not possible to transfer the valve characteristics under the above-mentioned conditions. Installation of a VGS repair kit is not permitted in this case.

Mercedes-Benz ML450

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