ok i installed a tweeter in the front driver door i used a knife to cut tbhe speaker wire while the car was on so the knife grounded it out didnt think nothing of it .so i got the speker working and thought that everything is cool.so drivingdown the road and then the speedomt goes to 60 then to 0 like all the time now,then the d4 light is blinking and the check engine light is on now

 

CHECK FUSES