An easy way to test individual relays is to use a suitable DC power supply (I simply use a common 9 volt battery; you can use your car's battery as well) and touch probes to the two small pins at the bottom of each relay. The individual switch should close. In the case of the traction control and engine control relays, they seem to function in tandem - if you energize one of them, both relay switches should close. With the RCM oriented so that the relays are facing up and toward you they are left to right 1) horn, 2) traction control, 3) engine control, 4) fuel pump, and 5) air pump.