If you are working on European vehicles you know that one of the most common procedures that you will need to perform after replacing a component is Coding. Coding can be used to adapt a part or control unit to the vehicle right through many scan tools without going on the internet. The Coding information usually resides on the scan tool so there is no need to do anything other than carry out the function from the scan tool. As you can see from our example from an Autologic scan tool (figure 1) there is a manual function that has been selected to code the control unit to the vehicle. Another example that comes to mind that is a very common procedure is coding of the transmission transfer case motor on a BMW X drive vehicle. Many vehicle owners forget the golden rule of making sure that they have all the same tread depth as well as tire style on all wheels of the vehicle. When a vehicle owner cheaps out by not installing four matching tires, they will damage their transfer case servomotor and possibly damage the transfer case. Take a look at what happened on this 2007 BMW 328xi (figure 2) when this vehicle owner only replaced one tire while leaving three others, which had different tread depths. After the vehicle was driven 5,000 miles or so he lost his “X” drive and had to go for an expensive repair along with four new tires. As you can see from the picture, the transfer case servomotor gear is completely stripped out. Our repair included draining and flushing the transfer case to remove debris before installing a new servomotor. The next step is very important and involves using a suitable scan tool that is capable of coding the servomotor to complete the job.
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Now that we got the Coding out of the way it’s time to look at programming and reprogramming and what’s needed to be successful. These procedures can be as a simple as ignition key reprogramming or updating software of a computer module. There are a few different ways to program modules from OE to aftermarket scan tool interfaces. You’re going to need the vehicle’s battery voltage to remain stable by installing a clean low AC voltage output battery maintainer. When working on European vehicles you will need to invest in a battery maintainer that is suitable for the vehicle. Some vehicles, such as some newer BMW’s, need a steady 14.6 volts with up to 90 amps depending on the model. Another precaution to follow is making sure you route the scan tool OBD II cable through the door without crushing the cable. This is usually done by leaving the door open after locking the latch lever on the door. If you route the cable through the open window, it may be crushed as the vehicle is being programmed due to the windows being activated during the programming procedure. Also on the list is making sure all accessories are off and insuring nothing is disturbed during the process. Remember that in many cases the procedure can take many hours. If anything is interrupted during the programing process there is a very good chance that the unit being programed will be damaged and will not be recoverable. A damaged controller on a European vehicle will be a very expensive mistake.
Now let’s take a look at an easy task—key reprograming—that you are most likely to encounter since keys and fobs are either broken or lost. Our example vehicle is an Audi/VW key reprograming procedure, which can be very easy or not. The procedure can range from using an existing key that has already been linked to the vehicle’s security system, to programing a new replacement key. If the key and fob have been previously linked to the vehicle, the following procedure will work on many Audi/VW vehicles. The procedure for a previously programmed keys and fob are as follows:
1. Make sure the batteries in the key fob are good.
2. Press and hold the unlock button on the remote.
3. While continuing to hold down the unlock button, insert the key into the ignition.
4. Turn the ignition to the on position, making sure the unlock button is still depressed for two seconds.
5. After two seconds have elapsed, turn the ignition off and release the button.
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