Hello, my wife was driving our 2010 ML350 and suddenly heard a loud explosion coming from behind her which she describes as sounding like a gun shot. Car was driving steadily about 80mph on highway. She says she didn’t hit anything and she is sure the sound came from inside the car. There is no damage I can find to any part of the car inside, outside, or underneath.

She thinks the ETD system (seatbelt pretensioner) may have deployed. Any way I can check this? If so, it would be a major electrical fault, which this car has not been without. SRS light on dash comes on when I start the car and goes off after a couple seconds, as normal. I used a OBD scan tool and don’t read any codes. Not sure if the SRS module can be accessed through OBD port. My scan tool did not bring it up. Thanks for any suggestions.

Rob

 

Was there a semi nearby? When one of their big, high pressure tires goes, it makes quite a racket.