I have checked the crash sensor on the connectivity using multimeter.There is a beep sound when both red and black probe is connected to NO and NC pins of the sensor.But,when the orange coloured
rubber tap is pressed, the beep is disappeared.There are 2 pins for the sensor,:
1) NC pin
2)NO/C pin
The sensors act as a switch with no external power required.It is the external input for the pic to detect the collision and sends a sms. Is my connection of sensors to PIC in attached circuit is correct ?