I replaced my diffuser with an aftermarket one and 4 out of 5 times when I start my car I'm getting Blind spot and collision detection inoperative messages. The car shop that did the replacement said the diffuser has nothing to do with the radar sensor, which is behind the bumper, but I've been reading all kinds of stuff - calibration, interaction with the parking sensors, etc etc. Most of it sounds BS, but I wanted to ask here as well. Could an aftermarket diffuser cause any problems with the blind spot and collision detection system?

 

Of course the shop will tell it has nothing to do with anything. The question is why your system failed when you did the subject replacement. Are there any sensors on your diffuser. Did they remove the bumper when they installed the diffuser? They must have hit something or made something loose which trigged the malfunctioning of your system. There is a sensor on my diffusor as seen on the picture. I installed a c43 diffuser with its exhaust tips all OEM.

 

No, I don't believe there are any sensors on my diffuser, at least sensors that have anything to do with blind spot. They said they didn't remove the bumper, and AFAIK there is no reason to when replacing the diffuser.

 

When did this issue start? Right after you installed your diffuser?

 

Yes right after I picked it up.

 

Well there you go. The shop must do the necessary to bring the car back to normal operation special that the feature in question is related to safety.