Relay - what is it and why is it doing it!?!

[Jules]

One of the relays in my GSi has recently started clciking over like crazy - I'm talking about a dozen times in a second sometimes!!
I've changed the relay and it still does it and it only happens when I go over a bump - So I know that it's not a relay problem and it more likely to be something like a loose connection hence why it only happens on bumps.
The relay is on the second row (Behind the main 3 relays for indicators, wiper intermittant delay and heated rear screen) and is the 2nd on the right - I've taken it out and it seems to make no difference that I've noticed also when it clicks over all the time it seems to make no difference - but it's there for a reason.

Any ideas as to firstly what this relay does, and secondly why it's going as fast as it is?

I do know that it's not the 'lights on' relay as I've worked that one out all by myself (Clever old me!!!)

[XZiBiT]

is it not the buzzer that tells you ya left the lights on?

[Jules]

I do know that it's not the 'lights on' relay as I've worked that one out all by myself (Clever old me!!!)

No it's not!!!

I've worked it out now - It's the hetaed rear screen relay so not too important - but fcuking annoying!!!

[m.d.]

it could be the connection to the back of the switch or the connection to the window. thats the only place i can think where there is a connection

[badnova]

it sound to me that you may have a wire touching on metal somewhere
not quite sure if the relay works on a nagative signal or a postive
if it a negative then thats what it could be

a relay consists of two separate and completely independent circuits. The first is at the bottom and drives the electromagnet. on your car, a switch is controlling power to the electromagnet. When the switch is on, the electromagnet is on, and it attracts the armature. The armature is acting as a switch in the second circuit. When the electromagnet is energized, the armature completes the second circuit and the light is on. When the electromagnet is not energized, the spring pulls the armature away and the circuit is not complete.

so if you have the wire from the switch which might be a negative but not sure if ther wire is bare and touching metal on th car it could be making it do that

but as i say im not sure and it only a sugestion