Has 141k miles and with the fuel pump is it possible to change the O-ring or is it better to buy a new fuel pump?

Also this electrical problem started after I got a
Coolant change is it possible that the shop could of pinched a harness/wire or posibbly got some coolant on something by accident? How can I check to see if the ignition switch is going bad?

I thought it was cause the weather was changing it was giving me eltrical problem but bought new battery and still giving me problem. One thing I notice is it's like the computer not recognizing the usual problem it had when I
Got it as well usually I have self
Level suspsion message on my car as the air compressor in the back is off but now most of the time it does not say anything in the cluster no message about it also well check alt in a few hours