Impact Signal

When the Restraints Control Module (RCM) outputs any of the fire signals it also outputs a impact signal to the Body Control Module/Gateway Module (BCM/GWM). The message is transmitted by the High Speed (HS) Controller Area Network (CAN) chassis systems bus.

The impact signal is also hardwired to:

• The Powertrain Control Module (PCM).
• The Body Control Module/Gateway Module (BCM/GWM).
• All door modules.
• Telematics Control Module (TCU) - If equipped.

On receipt of the impact signal, the PCM cuts the power supply to the fuel pump relay and the BCM/GWM switches into impact mode.

In the impact mode, the BCM/GWM:

• Activates all of the unlock signals of the vehicle locking system, even if the vehicle is already unlocked.
• Ignores all locking/superlocking inputs until it receives an unlock input, when it returns the locking system to normal operation.
• Activates the interior lamps. The interior lamps remain on permanently until they are manually switched off at the lamp unit, or the impact mode is switched off and they return to normal operation.
• Disables the rear window child lock input until the impact mode is switched off.
• Activates the hazard warning lamps. The hazard warning lamps remain on until cancelled by the hazard warning switch or the impact mode is switched off.

The BCM/GWM impact mode is switched off by a valid locking and unlocking cycle of the locking system.