{"content":[{"text":"If you own a BMW, there is a chance that the steering switch unit and steering angle sensor may \n fail. BMW Steering Switch Unit also referred to as SZL, center steering column switch, and \n switch unit in the steering column is a unit mounted on the BMW steering column where various \n switches including a wiper, turn signal, cruise control mounted. The steering angle sensor is \n integrated into the SZL unit. SZL and steering angle sensors can fail on any BMW, causing any \n switches to stop working or trigger various warning lights. When the steering angle sensor fails, \n it triggers warning lights; most often, the DSC lights can come on randomly or as you start to \n drive. When the SZL module or steering angle sensor fails, the car will drive fine, but you may \n not have traction control, stability control enabled, or functioning switches. To confirm read \n fault codes using a BMW scan tool. The great news is that there may be a possible inexpensive \n fix for this problem. You can even perform yourself. If you have been quoted hundreds of \n dollars for SZL replacement because ABS, DSC, traction control lights are on due to a failed \n steering angle sensor, you should first try cleaning the steering angle sensor as instructed \n below. Cleaning the steering angle sensor is easy and, in most cases, fixes problems related to \n warning lights on the dash. Note that BMW dealerships will not clean the steering angle sensor. \n If you have determined that the steering angle sensor is the culprit, we will show you how to \n remove the SZL, open up the steering angle sensor, and clean it. If cleaning the steering angle \n sensor fails, you can still save money by replacing the SZL unit yourself. Coding an SZL takes \n less than one hour. Ask your BMW dealer or mechanic to carry out SZL coding, steering angle \n sensor adjustment system function, and calibration. Replacing the SZL yourself is a lot cheaper \n than having an auto repair shop or dealer replace it. Replacing the SZL module is so easy you \n can change it on your driveway. The symptoms caused by a defective SZL are different than a \n faulty steering angle sensor. A steering angle sensor optical sensor in the SZL can fail and \n trigger various warning lights. If the SZL unit is defective, any of the steering column switches \n may stop working. Knowing which component is defective is important. The following \n symptoms are only a guideline. You must read fault codes to properly diagnose a BMW. \n Typically the problem starts with a random warning message on the instrument cluster, which \n may go away and come back again randomly. If you have any of the following, the culprit is \n usually the SZL module or the switch itself and requires replacement of the component. There \n are two types of BMW steering angle sensors. The cleaning procedure depends on the type of \n steering angle sensor installed on your BMW. As a rough guideline, most BMW before had a \n potentiometer steering angle sensor. While and newer use optical sensor. Up to around , BMW \n used a Potentiometer to measure the resistance and calculate the steering wheel position. This \n steering angle sensor can be cleaned with Electronic Contact Cleaner. The optical discovery \n time will build up a thin layer of dirt and oil. This layer can interfere with the optical sensor. \n When the laser sends light to the disk, the layer will block or diffract the light beam, in which \n case the steering wheel position can no longer be determined. Clean the steering angle sensor \n disk and reinstall it. Only use lint-free cleaning cloth. You can also use an eyeglass lens cleaner. \n Use a product similar to Meguiars Clear Plastic. Note that alcohol can cause a craze on plastic \n optical disks. It is better to use a product that is designed to clean discs and plastic. Once you \n are done cleaning and putting everything back together, start up the car and turn the steering \n wheel clock to clock. Restart the car and drive it a short distance, and the lights should reset. If \n the lights remain on, read codes with a BMW scan tool. Carry out steering angle calibration and \n clear the codes. If the DSC light stays on, carry out steering angle sensor calibration. If the DSC \n light does not get reset, read fault codes. The following part numbers are for reference only. \n Always verify the part number by removing your old SZL module or by calling the dealer. Note \n that part numbers will change if BMW introduced a new or upgraded steering switch unit. The \n clockspring is part of the SZL module, and they are usually replaced as one unit. The clock \n spring can be swapped, but it is not a simple job. Check the alignment on your BMW. Bad \n alignment can trigger DSC light warning. Many shops will perform a free alignment check. \n Lowering the car can also trigger the DSC light. Also, check the battery on your BMW. If it is not \n holding a proper charge, replace it. Depends on the year and model. Typically SZL needs to be \n coded. VIN programming may be required in some cases. Yes, the procedure is simple. No front \n end alignment is only required if the steering wheel is carried properly. Always have the wheels \n point straight ahead before calibrating the steering angle sensor. SZL and steering angle sensor \n need to be installed in the car, then you will have to carry out the steering angle sensor \n adjustment system function and calibration. Figure 1. The SZL module is mounted behind the \n steering wheel. SZL steering switch unit module is not the same as the steering angle sensor. \n The steering angle sensor is integrated into the SZL, but SZL has other functions and purposes \n than the steering angle sensor. BMW SZL module is often confused with the steering wheel \n button switch module, which is behind the airbag in the steering wheel and controls the \n steering wheel buttons. The SZL module is below the steering wheel and contains a telescoping","bbox":{"left":0.050964,"top":0.031288,"width":0.897981,"height":0.894159}}],"images_bbox":[],"images_bbox_not_text_overlap":[]}