Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Output of Crash Telegram
In the event of a collision involving triggering of the restraint systems, the Crash Safety Module sends a crash telegram to the users in the bus-system network. Parallel to this, the TCU is informed via a direct single-wire line to transmit an emergency call.
As a result, the respective control units perform the following functions depending on the crash severity:
| Function | Control Unit |
|---|---|
| Switch off electric fuel pump | Digital Motor Electronics DME |
| Switch off the auxiliary heating | Integrated automatic heating and air conditioning system IHKA (Not for US) |
| Release central locking | Junction box electronics JBE |
| Switch on hazard warning lights | Footwell module FRM |
| Switch on interior lights | Footwell module FRM |
| Transmit emergency call (only when airbag triggered) | Telematics Control Unit TCU |
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.