Check the spoiler fixing bolts. On my 2016 I had the same issue. Eventually realised the rear spoiler seems to rattle when I slam the hatch shut, then taking it with hands and wiggling it side-to-side I hear the squeak!My ‘15 CX-5 has a chirp/squeaking sound from the rear hatch door. Would it be the plastic moldings rubbing on the rear windshield? I’ve heard the clips can break and cause this noise?
Any fix I can do without going to a dealer?
Thanks