A short is detected on the loop: EST4 Trouble Code

What This Code Means

A shorted circuit has been detected on the Signature loop controller (SLC) wiring, which typically reports a trouble condition on all devices on that circuit.

Common Causes

1The loop is incorrectly wired (often crossed wires on a device base)
2A detector, detector base, or module is defective
3The insulation between conductors is nicked

Resolution Steps

To isolate the short, open the data loop at a point that will disconnect approximately 50% of the installed devices. After opening the loop, if some of the devices restore, the short is located on the portion of the loop that has been disconnected. If no devices restore, the short has been isolated to the first 50% of the loop. Reconnect the previously isolated portion of the loop and continue increasing or decreasing the number of devices on the opened loop leg until you isolate the device or wire segment causing the problem.