I looked through the repair manual and it does not reference "over inflation" triggering the TPM, nor would I think it would. 40psi is not "over inflated", most OEM tires are recommended to 50-55 psi hot running temp.

I would guess your 27 psi did the deed, especially if your reading was 27 on a hot tire. That would mean your cold psi was somewhere in the 22-24 range... Most tires will increase psi by 10% from cold to hot.