I believe you are simply testing the function of the controllers by grounding both relays in the controller via the test switch that would normally find ground in the detector to make sure you get a flight deck effect. Arm chair troubleshooting, I would have to see the schematic. Kidde/Fenwall or Systron Donner? A fail message is usually indicated as a result of the loop K/F sense resistance change, the length of the loops are critical. S.D. a loss of pressure in the loop triggers a fail, high pressure = warning.