Grand California coding

Many of you have probably never had any contact with the subject of coding. If you’re not a tech nerd or a gaming kid, this will probably remain the case in 99 percent of cases. But maybe we’ll change your mind a little today.

From the ECU to the OBD connector…

A modern car, such as the Grand California, is nothing more than a moving computer. Many people don’t even realize how much technology there is in such a vehicle. The on-board control unit communicates with the alternator, for example, because the lights are switched on and more power is now required. Or the engine control unit notices after a mountain pass that the engine oil is too hot and reduces the engine’s output. As you can see, an incredible number of components have to communicate and work together, which requires software. This software is stored on the individual control units and does its job there. The Grand California alone has over 20 control units on board. Perhaps it is now clear why the step, which is of course controlled by a control unit, sometimes makes a few problems.

Now every car built since 2001 has a so-called On Board Diagnostic port, OBD for short. This port can be used to connect to the above control units with the appropriate hardware and software.

If, for example, the engine control lamp lights up in your dashboard, let’s hope this never happens, there is a fault. This error is stored on a control unit and can be read out via the OBD connection . The workshop is then able to narrow down the fault and solve the problem thanks to the many hundreds of measurement data.

… for coding

In addition to fault localization, the control units can also be reprogrammed via the OBD connection. There are many software programs available on the Internet that can adjust the corresponding values. Programming or coding is necessary, for example, to tell the vehicle that a new battery has been installed after a battery change. This is important in this example so that the control units can process the data received from the battery correctly.

There are also a number of options for individualization through coding. For example, accessories that are actually subject to a charge can be activated in the Grand California, provided the necessary components are installed. The most prominent example is the subsequent and free activation of the lane departure warning system, which Volkswagen charges dearly for ex works.

We would like to share two really important use cases with you in the following:

Conversion to lithium battery with the software Car Scanner

The first point is to switch to a lithium battery in the control unit. We have already written about lithium batteries several times in our blog, and most of the lithium batteries available as accessories have a charging current of 100A. This can lead to limitations when simply replacing them in the Grand California, as the charging current of the Grand California is more than twice as high with a peak of 200A. Of course, all modern lithium batteries have a BMS installed that blocks these currents and prevents them from reaching the actual battery cells. But the alternator also always has to regulate, which is probably not good for either the battery or the alternator over the years.

Fortunately, there is a little trick here: you can use the Car Scanner app to switch the battery technology to lithium. This means that the control unit now knows that a lithium battery is installed in the vehicle. This conversion causes the charging current to be limited to approx. 80A.

KFG Reset

You must have heard about the KFG plug, which is supposed to be pulled so that one or the other problem, such as a non-extending step, is solved again, right?

Now there are two possibilities: firstly, you crawl into the passenger footwell and pull the KFG cable, which in the worst case can damage the control unit, or secondly, you simply restart the control unit using your cell phone. Option two sounds much better, doesn’t it?

Required hardware and software

As already mentioned in the text above, you will need hardware and software to carry out the KFG reset, for example. Don’t panic, with around 40 euros you will be able to carry out future coding and, above all, help yourself in problem situations.

The hardware is an OBD dongle from VEEPEAK, which you can buy at Amazon.

Buy here – https://amzn.to/40LYWT4

The OBD dongle from VEEPEAK is delivered without the necessary software, here is now a whole series of apps, which you can use. We have had good experiences with the Car Scanner app, which is available for iOS and Android. The app itself is free, but also has a Pro version that unlocks more features. The costs for the Pro version are 8 Euro.

KFG Reset with Car Scanner

In the following we describe the OBD reset with the help of Car Scanner. The adapter must be connected to the OBD interface of the Grand California and the ignition must be switched on.

1. Start the app and connect to VEEPEAK by selecting the “Settings” item.
   

2. Select the VEEPEAK in the settings under the item “Adapter”.
   

3. Select Volkswagen OBD-II (MQB) in the settings under the item “Connection profile”.
   

4. Select “Coding & Service” in the main menu.
   

5. Select the “Long coding” item and click on the “3D Special Function” control unit.
   

There you will now find Soft & Hard Rest. Both are used to restart the KFG control unit. Please always use the soft rest first; you can think of it as the normal restart of your PC. However, if the control unit does not respond to this, use the Hard Rest function. This is similar to the reset button on a PC.

The control unit then restarts and there is no need to disconnect the plug.

If you have any questions about VEEPEAK, Car Scanner or the instructions. Just write them in the comments.