IP 5s wont stop vibrating after waterdamage

If it's a small project and you don't need the phone urgently I would consider doing things properly, i.e. removing shields and cleaning the logic board thoroughly with isopropyl alcohol >90%. Without a good clean chances are your phone will be short lived, maybe weeks or months but if any liquid got under the shields corrosion has already started and will continue eating up components and power rails. The vibrator can be removed, but fact it's always powered means you got a short somewhere. I'd check the switch and try replace the flat cable connecting it to the logic board in case the cleaning doesn't solve the issue.