Failed inspections; Bad obd2?
 

I'm having a weird issue guys. 2 different jiffy lubes said they're obd2 machine can't connect to my obd2. Code readers connect just fine. Today I went for inspection and the guy said he checked my fuses but he still can't connect. Upon disconnection I got a check engine light I don't remember the code but It looked like p554 (that's not right but close enough). A separate scanner connected and code read "system voltage low". The only thing I've done that could have sparked this problem was having a system installed in January which is no longer installed. Could my odb2 be bad? What should I do I dont have any ideas?

Same thing happen to me, except i changed my Cigarette outlet fuse to a lower amp fuse to temporally be able to charge my phone (only spare fuse I had at the moment). OBD2 scanners couldn't read either... until I replaced the correct fuse.

Triple check your fuses, replace any questionable ones.

Thanks for your response I will definitely check them again. Back in February I changed all of the fuses in the box inside the car and few under the hood box.