I have a loud buzzing noise coming from the general vicinity of the engine bay fusebox, it sounds to me like a malfunctioning relay, there does not appear to be anything otherwise wrong with the car. Compared to other vehicle related things I have found my search results are completely saturated by parts for sale and I am not really getting anywhere which is why I am asking here.

My question is, is it reasonable for me to pull each relay and in turn, switch the ignition on to test if I have pulled the offending part? This may be a stupid question but if I can sort this quickly and easily but for want of a little knowledge then it would be stupider not to ask, even stupider to start messing around with it if there is a risk of causing damage.

Thanks!