Drivers Airbag

Drivers Airbag

The drivers airbag can deploy in one of two stages, depending upon the severity of impact. If a less severe impact is detected, stage 1 deployment is carried out. The SRS DCU (C0256) provides a firing signal to the drivers airbag (C1254) via the rotary coupler (C0082) on a YB then S wire. The SRS DCU (C0256) provides an earth path for the drivers airbag (C1254) via the rotary coupler (C0082) on an LG then YN wire.

A split second later, the SRS DCU (C0256) provides a second firing signal to the drivers airbag (C1254) via the rotary coupler (C0082) on an SN then U wire. The SRS DCU (C0256) provides a second earth path for the drivers airbag (C1254) via the rotary coupler (C0082) on a US then SB wire.

When stage two deployment is required, the SRS DCU provides simultaneous firing signals to both squibs as described previously.

Passenger Airbag

The passenger airbag can deploy in one of two stages, depending upon the severity of impact. If a less severe impact is detected, stage 1 deployment is carried out. The SRS DCU (C0256) provides a firing signal to the passenger airbag (C0251) on a UN wire. The SRS DCU (C0256) provides an earth path for the passenger airbag (C0251) on a UB wire.

A split second later, the SRS DCU (C0256) provides a second firing signal to the passenger airbag (C0251) on a WB wire. The SRS DCU (C0256) provides an earth path for the passenger airbag (C0251) on a WN wire.

When stage two deployment is required, the SRS DCU provides simultaneous firing signals to both squibs as described previously

Door Airbags

The SRS DCU registers a side impact via the side impact sensors, which are mounted at the base of the LH and RH B/C posts. The SRS DCU monitors the condition of the RH sensor (C0951) and the LH sensor (C0950) on YR and YG wires respectively. Both sensors are earthed on NB wires. When the SRS DCU registers a side impact above its threshold level, it will fire the relevant door airbag.

The SRS DCU (C0256) provides a firing signal to the RH door airbag (C1499) on a U wire. An earth path is provided by the SRS DCU (C0256) on an N wire.

The SRS DCU (C0256) provides a firing signal to the LH door airbag (C1499) on an N wire. An earth path is provided by the SRS DCU (C0256) on a Y wire.