feature Keep the Lights On By Frank Walker Here are tips for diagnosing BMW computer-controlled Intelligent Headlight technology, including intermittent or flickering lights, lens cracks or condensation in housings, and plugged headlight washer nozzles.

BMW Intelligent Headlight systems feature adaptive lighting technology that responds to different driving conditions. The state-of- the-art lighting provides better illumination for night driving, highlights pedestrians and potential obstacles in the road and, depending on the BMW model, reduces glare into the eyes of oncoming drivers. These computer-controlled lights may experience rare problems such as flickering while driving, flashing on and off at ignition startup, trapping moisture inside the headlight housings, and developing cracks in the lens covers. We’ve collected a few tips to help understand the causes and show where to find repair information. Unless otherwise noted, all repair information in this article is based on instructions found in various Service Information (SI) bulletins published by BMW. Refer to the BMW Technical Information System (TIS) for model- specific repair procedure details.

When following any of the tips provided here, always connect a BMW-approved battery charger/power supply (refer to BMW SI B04 23 10 for list of approved chargers) before starting repairs to the LED headlight system. A steady power supply is absolutely critical to the success of any effort to reprogram, encode, or initialize a control module after repairing an adaptive headlight system. Note that charging parameters must be set manually by the user, and procedures vary based on the battery type and which charger is used.

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october 2020 27 Keep the Lights On 1. Headlight flickers A poor connection could also specific information searches cause faulty communication and guided troubleshooting. while driving between the headlight and the Refer to the BMW Tech Info On BMW F-Series vehicles LHM2, even if the headlight website for subscription details. produced up to September is not failing. In that scenario, 2014 with option 552 (adaptive the controller receives function If communication fault codes LED headlights), you may get status signals that don’t match have been set in the Body a customer complaint that the factory performance parameters Domain Controller (BDC), in headlight on one side flickers for the headlight. Code 8044BB the Footwell Module (FRM), or on and off while driving. The sets if the right-hand LHM2 in the LED main light module problem, which applies to the receives an implausible low (LHM2), work through the repair BMW X5, X3, 4 Series Coupe, beam function status. A code procedures for those codes first. and 4 Series Convertible, may 8044BA is stored if the left-hand Eliminating a communication be intermittent. Check the TIS LHM2 sees low beam data that error may clear up other problems bulletin SI B63 09 14 “LED does not match specifications. without requiring replacement Headlight Malfunction” for details. of the control module or When any of the four codes other major component. This situation is typically mentioned are stored, a Check caused by a poor connection, Control message indicates that If checking and repairing any not a defective headlight. The a problem exists within the communication faults does not connectors at either the LED parking or driving light system. eliminate headlight operating headlight or the LED main light problems, perform the BMW test control module (LHM2) end of plan (“ABL_DIT_AT6300_BDC_ the circuit could be loose. Repair procedure Perform a vehicle test using LED_SCHW” in ISTA) to swap The low or high beam headlight ISTA. The ISTA scan tool soft- the left and right LED main light could be affected. If it is the ware offers powerful BMW and modules. You will have to pull low beam, the system will Mini vehicle diagnostic (ISTA/D) the front bumper (ISTA repair store an 805980 fault code. and reprogramming (ISTA/P) 51 11 156 “Removing and in- An 805981 code is set for capabilities, plus vehicle iden- stalling front bumper panel”) to a high beam problem. tification assistance for highly access the LHM2 modules.

On the LED headlight, check to confirm that the Lift the connector up until you hear a clicking sound. connector is down to the position shown in the picture. The click means the locking tab has engaged and the If it is not, push the connector all the way down. connector is properly and securely positioned.

28 the bimmer pub If the problem moves to the modules to opposite sides, check To prevent the connector from opposite side when you swap to make sure the connector on becoming loose again, apply the LHM2 modules, the module each LED headlight is properly an adhesive to the locking tab that the error follows is defective positioned and not loose. before reinstalling the headlight. and must be replaced. Remove the LED headlight. Push its connector down, then pull it 2. Low beam flashes If the lights function correctly back up until it locks into place. after switching the LHM2 Do the same for each headlight. briefly after startup On BMW F-Series vehicles produced from August 31, 2008 to July 9, 2014 with option 552 (adaptive LED headlights), the LED low beam headlight may flash briefly once the ignition is on. The problem applies to the BMW 7 Series Sedan and Sedan LWB, 6 Series Coupe, Gran Coupe and Convertible, 5 Series Sedan and Gran Turismo, and the X3 (F25).This issue can occur each time the vehicle is started. See the TIS bulletin SI B63 11 14 “LED Low Beam Flashes Briefly After Ignition Switched ON” for additional details.

Apply adhesive behind the tabs (see red arrows in picture) on When the LED low beam headlight begins flashing on and each side of the connector. Do not place glue along the long edge off, the system may store one or of the connector (red “x”). Before applying the glue, clean the both of the fault codes 0xDA1411 area per the instructions from the adhesive manufacturer. Apply or 0xD9D411. Both faults reflect adhesive to both sides at the same time, and only after the tab is a problem with the operational in its locked position. After ten minutes of drying time, reconnect status of the headlights. The the LHM on both sides. Confirm that the headlight works before codes are set when the operating completing installation into the vehicle. Reinstall the front bumper function signal that is transmitted from an LED main light (LHM2) and delete any stored headlight fault codes. module is invalid or does not fall within parameters set in Use the BMW- the control module software. approved K6 The cause of the problem is adhesive set (83 typically a faulty LHM2. 19 2 317 925). One set covers Repair procedure two vehicles. Diagnose the fault by performing a vehicle test using ISTA/D. If both fault codes 0xDA1411 or 0xD9D411 have not been set or stored by LHM2, follow the diagnostic instructions in the ISTA/D test plan. If the test shows that both codes have

october 2020 29 Keep the Lights On been set, replace both LED main headlight modules.

To access the LHM2 module, pull the front bumper (ISTA repair 51 11 156 “Removing and installing front bumper panel”) and remove the headlight assembly (ISTA repair 63 12 140, “Removing and installing left/right headlight - LED technology”).

Remove the LHM2 per ISTA repair instruction 63 11 800, “Replacing LED main light module left.”

Reprogram the BMW X3 models produced from October 2010 to June of 2012 control module may develop stress cracks in the headlight lens covers. The cracks After installing a new LED often begin at the lower edge of the lens cover and spread upward. headlight, you must reprogram the control unit to enable communication with the Install only headlights replacement light. In the ISTA/P program/encode produced in menu, select the control unit November, 2012 or you replaced (LHM2_R or later. They feature LHM2_L), or both, to initialize. a new, more crack- resistant design. In NOTE: ISTA/P will automatically update coding for all the sample label here, programmable control modules the production date that are not already using the is highlighted in red. latest software version. For more The first two digits are information on programming the month, the third using ISTA/P, refer to CenterNet/ and fourth are the day, Aftersales Portal/Service/ and the fifth and sixth Workshop Technology/Vehicle Programming in the BMW TIS. digits are the year. 3. Stress cracks in This fault in the lens cover may press too tightly against the headlight lens cover material has two different top of the headlight housings Second-generation BMW F25 potential causes. One is bump when the hood is closed. (X3) models produced from stops (pedestrian safety buffers) September 30, 2010 to June 21, 2012 may experience stress that are cracked, misaligned, Repair procedure cracks in the headlight lens or missing, and cause the front Replace only the headlight on covers. See TIS bulletin SI B63 of the hood to weigh down the damaged side. Refer to ISTA 03 13 “Stress Cracks in Headlight excessively on the headlight lens REP 63 12 010 “Removing and Lens Covers” published in cover. Another source of stress installing or replacing headlight” March 2013 for details. is old design hood lip seals that for repair instructions. Install

30 the bimmer pub only a headlight produced on 51 23 “Installing/Replacing Beginning with June 20, 2012 or after November 10, 2012. bump stops” for procedural production of the F25, BMW details. NOTE: Ask for the introduced a new dual-chamber, After replacing the headlight, vehicle’s recent repair history. reinforced seal designed to check and replace any cracked, The bump stops may be prevent the front lip of the hood misaligned, or missing bump out of alignment due to an from applying excess pressure stops. Refer to ISTA REP incorrect previous repair. on the headlight housings when closed. If you are working on a vehicle with the pre-June 2012 seals, replace them with the new design. After your repair, check to make sure the hood does not come into contact with the headlight housings. 4. Condensation or water droplets inside the headlight housings A customer may complain of moisture inside the headlight assembly. Your inspection will

If bump stops (pedestrian protection buffers, circled in yellow) are damaged or incorrectly positioned, they may allow the front end of the hood to press down excessively on the headlight housings, causing cracks and fissures in the lens covers.

A

B Large droplets of water (A) inside the headlight lens cover are caused by leaks passing through failing seals or cracks in the housing. A Replace the old design seals (see yellow circles) on the left and right fine mist (B) is due to the natural sides of the hood front lip with new dual-chamber reinforced sealing. process of condensation.

october 2020 31 Keep the Lights On reveal either a fine condensate condensation on the inside in the solution. The hardened mist or large droplets of liquid of windows in your home, material prevents a seal from inside the headlight housing. which you’ll notice more in seating properly, and allows Look for TIS bulletin SI B63 the cooler months than the fluid to leak from the nozzles. 05 16 “Headlight Assemblies summer. So condensation is a Information in this bulletin (SI Have Visible Internal Moisture/ natural process, not a defect. B61 14 16) applies to vehicles Condensation” for further details. produced up to March 31, 2015. The problem and repairs An easy fix If the headlight lens is cracked The solution is to replace the discussed here apply to all or a seal is failing, replace windshield washer reservoir and BMW headlights in all BMW the damaged component. If filler pipe, flush the system, and models, including the i3, i8, condensation is the problem, then install new washer nozzles, and the 7 Series Hybrid. the solution is to dry out both in that order. You don’t want to This problem can be caused headlights. See BMW TIS place new jets in until all other by either a moisture leak Service Bulletin # SI B63 05 16 components have been flushed. into the headlight housing (published in March of 2018) or condensation. How can for repair procedure details. Repair procedure you tell which has occurred? You’ll need three different Run the high beam to clear A leak will appear only on out the condensation. If after repair instruction documents. the headlight side that has 30 minutes there is still a mist 1. ISTA/AIR 6171061 “Replacing a weakened seal or cracked inside the lens, open all the washer fluid reservoir for housing. If the problem is due service covers in the headlight windscreen washer system” to condensation, you will see assembly and, using a hot air misting in both headlights. 2. 6167122 “Removing and blower, dry out the light. Do not Additionally, a leak shows large installing/renewing right let the temperature exceed 80 high-pressure nozzle of droplets, while condensation degrees C (176 degrees F). appears as a fog or mist. headlight cleaning system” After the repair, check your 3. 6167120 “Removing and Condensation work. Make sure that the installing/replacing left is natural headlights function properly. high-pressure nozzle of If you see lime scale, crusty headlight cleaning system” All air, even that inside a edges, or other permanent sealed compartment such as water stains on the lens, replace When done, refill the system a headlight, contains some the affected headlight. with 5 liters of windshield amount of moisture in the form washer cleaning fluid. Verify of water vapor. Condensation Reassemble the lens cover that the headlight cleaning occurs because cool air cannot and attachments on the function works and check that hold as much moisture as headlight. Make sure that the the nozzles do not leak. warmer air. A quick chill in the seals and rubber grommets weather can cause a temperature are in their correct locations differential between the inside and are firmly seated. Reinstall Always check and outside of the headlight, the headlights per the for bulletins creating ideal conditions for instructions in the BMW TIS. All of the information in this condensation to develop. article was extracted from service When warm, moist air inside the 5. Headlight cleaning bulletins published by BMW. The headlight touches the cooler nozzles leak Technical Information System surface of the lens cover, the When a customer complains (TIS) at www.bmwtechinfo.com air cools, and some of its water of washer fluid leaking from is the best source for factory- vapor condenses onto the the headlight cleaning jets on approved diagnostic and repair surface. The same principle a BMW F25 (X3), the cause is information. Use it and help your is behind the formation of typically calcification of minerals customers keep their lights on. •

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