Safety Circuit
The task of the safety circuit is to detect faulty signals in the control module and faults in the electrical cabling system.
The following components are monitored continuously:
- BAS solenoid valve (A7/7y1)
- BAS diaphragm travel sensor (A7/7b1)
- BAS release switch (A7/7ys1)
- Stop light switch (S9/1).
If a fault is detected, the system switches off. This is indicated to the driver by lighting the malfunction indicator lamp: BAS, BAS/ETS, BAS/ASR or BAS/ESP malfunction indicator lamp (A1e39, e49 e48 or e47).
In addition, a fault code is stored in the control module.
Moreover, the safety circuit continuously monitors the battery voltage. If the voltage falls below 10V or exceeds 16-18V, the system is also switched off until the voltage returns to the specified range.