Is the fuse good? Follow the orange wire from the relay there will be a fuse holder. If the fuse is good check for voltage on the orange wire, gets power from the horn relay, and on the dark blue wire, gets power from the speed switch when high is selected, also check for continuity to ground on the small 16 ga black wire. If the relay gets power on the orange wire, has power applied to the relay coil on the dk blue wire and the relay is grounded via the black wire you should get power out to the blower on the purple wire.