In recent years, there has been a tremendous development of so-called assistance systems that increase the safety and comfort of driving and the popularisation of electric and hybrid vehicles. The development and implementation of new technologies is most often associated with changing the existing solutions due to emerging limitations.
Over the years, manufacturers used vacuum to control many actuators (e.g. turbocharger control) and to increase braking power. Huge requirements and market trends, including popularised electric and hybrid vehicles, forced the introduction of a new type of system, e.g. the BOSCH electromechanical brake booster iBooster [Fig. 1.]. Note that this is the second generation of the brake booster that is produced in Poland. This system is installed, among others, in Volkswagen AG, TESLA and PORSCHE vehicles. Functions that can be implemented thanks to this solution include:
Each technological change brings challenges and potential additional problems for independent workshops when servicing or repairing. The process of replacing or disassembling the BOSCH iBooster brake booster requires following procedures in order to ensure correct operation of the system after external interference. In order to bring this issue closer, the article presents the iBooster replacement procedure carried out on the VW Arteon vehicle.
The iBooster electromechanical brake booster has a separate diagnosable control module. Fig.4. shows the possibilities that are available in the ESI [tronic] 2.0 diagnostic software by Bosch [Fig. 4]. Among other things, the following are possible:
During the replacement/diagnosis of this system at Volkswagen AG, additional procedures are required, not included in the universal software (Fig. 5.), such as:
In this area, independent workshops have the option to use diagnostics using the vehicle manufacturer’s factory software, with the support of the standard SAE J2534 with Pass-thru interface (this was described in detail in the article “Pass Thru group VW, Audi, Seat, Skoda”).
Replacing the brake booster requires the workshop to perform procedures through the Offboard Diagnostic Information System Service (ODIS) software. As mentioned earlier, this component has a separate control module. After removing the damaged electromechanical brake booster module and installing a new one, perform the following functions using a diagnostic proof point:
a) Coding of brake booster control module -J539-.
b) Bleeding the brake booster.In order to effectively bleed the system, the following conditions must be met:
Next, start the connected device for bleeding the brake system, set the working pressure in the range of 1.5 to 2.5 bar, unscrew the left front brake caliper bleeder and the right front brake caliper bleeder until no air bubbles appear in the hose from the used brake fluid reservoir.
In the next part of the program, the brake booster will be bled. Remove all objects from the driver’s footwell due to the program automatically activating the brake lever check. In the next steps, we are asked to unscrew the vent of the indicated brake caliper and confirm its readiness and then close it [Fig. 7].