These relays send power to the fuel pump and fuel injectors when the key is turned to the “ON” position. So, when they fail, there is no electrical current to the necessary fuel system components to send fuel into the engine, causing engine stalling or failure to start.
In this situation, there are many other possibilities, so testing components is vital for time and money savings.
If the relays test bad, they must be replaced with relays specific for that circuit.
To help prolong the life of your under-hood electrical components, ensure the lid for the fuse block is closed, and any factory sealing material is correctly installed.