The airbag sensor in your PT Cruiser monitors the function of your airbag. The airbag is an important safety device in your Cruiser. If the sensor is malfunctioning, then your airbag may not deploy properly in a crash. It's important that you have the airbag assembly serviced by a professional mechanic to make sure that it is restored to working condition. Once the airbag assembly has been fixed, you need to reset the sensor. This will also cause the warning light on the dash to reset and go out.
Open the hood and loosen the nut on the cable clamp that is connected to the negative battery terminal using a socket wrench.
Slide the cable clamp off the negative terminal.
Wait five seconds and reconnect the negative battery cable to the battery terminal.
Tighten the retaining nut using a socket wrench. Verify that the sensor has been reset by turning the ignition key to the "II" position and wait for the airbag sensor warning light to go out.