To check the history of the control panel enter the Master pin and enter # 89. If the system shows a SYSTEM FAULT 04, follow the steps below:
Solution: Start by disconnecting the field wiring from each terminal while watching the keypad display. The keypad power light should stop flashing when the ground fault is removed.
If a keypad is not present at the control panel, use a voltmeter to find the ground fault:
Connect the negative lead to terminal 1 or 2 panel ground.
Connect the positive lead to terminal 8 AUX Power.
Voltmeter should read between 6.5 VDC and 7.5 VDC. A reading that is higher or lower indicates a ground fault.
Remove the field wiring from the control panel while watching the voltmeter. When the voltage returns to the normal voltage of 6 .5 VDC to 7.5 VDC, you have found the wire that is causing the ground fault.