88C-3
MR-372-J84-88C100$059.mif
V5
AIRBAG RC5
Vdiag: 14AIRBAGS AND PRETENSIONERS
Fault finding – Introduction88C
3. REMINDERS
To run fault finding on the vehicle's computers, switch on the ignition in fault finding mode (forced + after
ignition feed).
Proceed as follows:
– with the vehicle card in the RENAULT card reader,
– press and hold the Start button (for more than 5 seconds) with start-up conditions not fulfilled,
– connect the diagnostic tool and perform the required operations.
To cut off the + after ignition feed, proceed as follows:
– disconnect the diagnostic tool,
– press the Start button twice briefly (less than 3 seconds),
ensure that the + after ignition feed has been cut off by checking that the computer indicator lights on the instrument
panel have gone out.Note:
The left-hand and right-hand xenon bulb computers are powered when the dipped headlights are lit. Therefore
fault finding can only be carried out on them after the ignition has been switched on in fault finding mode (forced
+ after ignition feed) and the dipped headlights have been switched on.
88C-11
MR-372-J84-88C100$118.mif
V5
88C
AIRBAGS AND PRETENSIONERS
Fault finding – System operation
The purpose of the air bag system RC5 P1/P2 is to provide optimum safety protection for all of the vehicle
occupants.
Special notes:
The MEGANE is equipped with driver and passenger seat belt buckle pretensioners in the front section.
The MEGANE is equipped with an "anti-submarine" airbag inside the seat base
The MEGANE is equipped with driver and passenger chest-level airbags in the rear section.
On MEGANE phase 1,
Warning light management: the status of the airbag fault warning light takes priority in relation to the status of
the passenger airbag warning light.
Impact management: a single level is emitted over the CAN line.
On MEGANE phase 2,
Warning light management: the two warning lights cannot be separated and the status of the passenger airbag
warning light is maintained when the airbag fault warning light illuminates.
Impact management: two levels of separate impacts are emitted over the CAN line.
Frontal impacts:
This function is performed entirely inside the computer. Accelerometers measure the violence of the impact. Vehicle
speed, driver's seat position, passenger airbag locking switching position and the accelerometer measurements
determine the strategy that the computer adopts to trigger the ignition modules. The front and rear seat belt inertia
reels, the front seat belt pretensioners, the face air bags (levels 1 and 2) can also be triggered or not according to
the entry parameters.
Side impacts:
This function is performed by the computer and the side impact sensors.
The position of the passenger airbag locking switch and the accelerometer measurements determine the strategy
that the computer adopts to trigger the ignition modules. The seat belt inertia reels, the seat belt pretensioners,
the front chest airbags and the curtain airbags thus may or may not be triggered.
Seat belt locking monitoring:
This function is performed by the instrument panel. The computer only sends the driver's seat belt buckle sensor
status. A warning light on the instrument panel is displayed if the driver is not wearing his seat belt, and a buzzer
reminds the driver of this when the vehicle speed exceeds 12 mph (20 km/h).
Inhibition of passenger trigger lines:
This function is performed by the computer and the passenger airbag locking switch.
The choice of whether or not to deactivate the passenger airbags must be made before the vehicle speed exceeds
0.3 mph (0.5 km/h). The computer measures an impedance (100Ω= Passenger Airbag deactivated;
400Ω= Passenger Airbag active). Above the threshold, any action on the locking switch results in storage of
the fault DF193and the instrument panel warning light is illuminated.
The front passenger airbag (levels 1 and 2), the passenger lap belt pretensioner and the front passenger
chest-level airbag are deactivated when the locking switch is in the OFF position or when the fault
DF193 "Change of passenger airbag locking status" is present in the computer memory.
Monitoring the information displayed on the instrument panel:
The instrument panel controls the correct working of warning lights "air bag failure" and "air bag OFF" and informs
the air bag computer about possible warning light circuit failures through the multiplex network.
AIRBAG RC5
Vdiag: 14
