Hi Does anyone know what this relay does? It is the one that clips to the very top of metal housing that the beige relay box sits into. It is warm even though car has not been used, when removing it the car won't turn over, interior lights come on as normal but they go out when trying to turn over car
. I swapped it but the other gets warm too. My parasite draw goes away when this relay is removed.

 

Its a 2003 blob sti uk

 

There is also a "Security Relay" back there with a 4 pin blue plug

 

That's the one, it had a blue plug. I take its normal for that one to be warm as its meant to have power to it as it did with ignition off

 

With the ignition on it will be continuously energised to hold the contacts in for the starter solenoid circuit as and when needed. (key - start position)
When the car is alarmed it should drop out being one of the immobilised circuits controlled by the alarm ECU.
It is fed direct from the battery via fuse No2 in the main fuse board under the bonnet.