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 |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.