yorxs, you need to unplug the five plugs and remove the board from the enclosure. Google "crossfire relay board" and select images. Lots of pictures of the board and relays. Based on my experience you need to have a very close look at the solder joints associated with the relays. In my case I first used a standard magnifying glass the first time and missed the fact that there were poor solder joints on the relay associated with the Secondary Air Pump. Use the highest magnification you can when checking. As tighed1 says it may be difficult to find just one relay without meeting a minimum order charge that doesn't make sense.