if the relay has a contact layout imprinted on it check the n.o. contacts with a meter and see if there closed . if all check ok check the coil for the relay should read 30 ohm or some where in that range but not zero ,if it reads zero its shorted and will blow a fuse .......dont be fooled by the diode it may read zero in one direction and 30 ohm in the other direction (the diode is there to collapse the field once the relay is shut down, but is usually installed with a reverse polarity to shunt the field .)