47
SSP217_059
5 V/Div. 0,5 s/Div.
Recorder mode
Crash signal
with triggering
Triggering range
Crash signal
SSP217_058
T
5 V/Div. 0,1 s/Div.
In the event of a crash where the belt
tensioners/airbags are triggered, the engine
control unit deactivates actuation of the fuel
pump relay. This prevents excessive quantities
of fuel escaping if the fuel system is damaged.
The crash signal is a square-wave signal with a
specific signal ratio (high level to low level).
The signal is transmitted continuously by the
airbag control unit.
In the event of a crash, the signal ratio is
inverted for a defined period of time. During
this period, the signal ratio is inverted relative
to the standard signal so that the supply of
fuel is shut off until the engine is restarted.
In addition, the “crash shut-off“ fault is
stored.
The fault entry can only be deleted
using the diagnostic tester.
Automatic mode
Standard signal
Crash triggering
Signal traces for crash signal using oscilloscope
function of VAS 5051
To Next Page
Loading...
