Canon EF 100-400mm 4.5-5.6 L IS issue

I was shooting an outside event with this lens on my 7D II. I was in high speed shutter mode all day Saturday and Sunday. On Sunday morning, started to notice some slow focusing and shutter response, and then late Sunday morning the camera refused to shoot.... switched the lens to my 7D and it also did not fire. Was in the middle of the job so I put on my 70-200mm F2.8 II and it worked fine, saving my a$$.

I'm getting ready to send the 100-400 in to CPS today, it now it appears to be working flawlessly.

Should I send it in for an eval anyway? I hate to take it out on another job and have it fail again.... but also am concerned that if I send it into CPS they will not find anything wrong with it.

Advice?

Might be something is starting to fail - intermittently - so better to have it checked. Without some specific symptom it is better not to speculate and let them go over it thoroughly.

Oops... need to add that it would not fire in AF mode, but fired in MF.....

You may want to try cleaning the contact points on the lens. It could be the beginning of a problem, or it could just be dirty contacts.