Workshop notes from 18 October 2026
An injector output that would not switch off, a BMW head unit caught in a restart loop, and three different DSG jobs. These are examples of work carried out at AXION Automotive, alongside SRS module data work on a 2021 BMW 4 Series. Each needed a different response.
Mercedes-AMG G-Class ECU with an injector output stuck high
The injector-driver output stayed high instead of pulsing and switching off. We traced the problem to the clock line to the MCU, the microcontroller inside the ECU, and repaired the ECU.
The useful detail in this job is where the fault was found. The symptom appeared at the injector output, while the fault we identified was in the clock line to the controller. It is a specific example of the circuit-level investigation involved in ECU repair. It does not mean that every injector switching fault has the same cause.
For this type of enquiry, see ECU testing and component-level repair. Send the ECU label and describe what the output is doing, along with any diagnostic report you already have.
2021 BMW 4 Series SRS module data work
We carried out crash-data reset work on the SRS module. The job involved reading its stored data, modifying the relevant data and writing it back to the module.
This note describes the module data work only. It is not a statement that the complete restraint system has been repaired or certified safe. Airbags, pretensioners, wiring and the required vehicle checks remain part of the vehicle-specific repair process.
Read about SRS module assessment and supported crash-data work. Suitability depends on the exact module and the vehicle manufacturer’s repair requirements.
2021 BMW 2 Series head unit repeatedly restarting
The head unit kept restarting over and over. We repaired it by upgrading the software and reflashing the firmware.
A restart loop is a symptom, not a diagnosis. This job was resolved through software work; another unit with similar behaviour still needs its own assessment. See module programming, coding and software support.
DQ200 and DQ500 control-unit cloning
We also completed two separate DSG control-unit cloning jobs, one for a DQ200 and one for a DQ500. These were cloning jobs, distinct from the sensor repair described below.
If you need similar work, send identification for the original unit and any proposed replacement. The gearbox family alone is not enough for us to confirm a particular job. Include the full part numbers and tell us whether the original unit can still communicate.
DQ381 pressure-sensor replacement and backup
The DQ381 job involved replacement of a pressure sensor and a data backup. It was a different scope from the DQ200 and DQ500 cloning work, despite all three enquiries involving DSG electronics.
For pressure-related faults, include the complete scan and previous diagnostic findings with your enquiry. We need to establish the work required for your unit before agreeing a repair. See TCU testing, DSG electronics repair and supported cloning.
Have a similar problem?
Tell us the vehicle, the affected module and what happens when the fault occurs. A clear label photograph and the full diagnostic report are useful if you have them. If you do not have a part number, describe the symptoms and we can discuss the next step.
AXION Automotive is based in Didcot, Oxfordshire. We support vehicle owners and garages, with UK-wide postal and remote arrangements for suitable work. Contact us before sending a unit or travelling to the workshop.
Send a repair enquiry or call 07440 134303. For current assessment options, visit repair assessment appointments.