Connector Position Assurance Locks
WARNING: This page is about a different car, the 2004 Suzuki Swift + and 2004 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to ensure good contact between the SIR mating terminals.