The fault message No loop signal is displayed when the Automower® robotic lawn mower is not able to detect the loop signal from the boundary wire.

1. Actual break in the wire
   
2. Bad connection at the charging station
   
3. Damaged or water penetration at splice couplers
   
4. No power or wrong voltage to the charge station
   
5. Faulty charge station board

Diagnostic steps:

1. Make sure power outlet is working
   
2. Make sure power is connected correctly to charging station
   
3. Confirm charging station has Flashing Blue Light
   
4. Take a short length of wire and connect AL to AR connectors (see if light turns green)
   This will confirm issue is with the wire and not the charge station
5. Check the resistance of the perimeter loop with a multi meter (set to ohms/Omega symbol) just unplug the perimeter/loop wire from the charge station, then take at reading at the 2 connection points/wire ends (AL and AR). It should read about 2 ohms per linear 100m (330ft).
   
6. Check for bad connection/corroded wires at charge station and any splice couplers.
   
7. Walk the perimeter to look for any obvious breaks or signs of damage to lawn
   
8. You can purchase a Wire Break Locator Kit to help find breaks:
   
   https://autmow.com/product/autmow-wire-break-locator-kit/
   
   
9. Using Boundary and Guide Wires to narrow down search: Follow below steps:
   Note: This method does not work if ECO mode is activated. Make sure first that ECO mode is off.

1. Check that the indicator lamp in the charging station flashes blue, which indicates a break in the boundary loop.
   
   
2. Check that the boundary wire connections to the charging station are properly connected and not damaged. Check that the indicator lamp in the charging station is still flashing blue.
   
   
3. Switch the connections between the guide wire and the boundary wire in the charging station.
   Start by switching connection and…
   If the indicator lamp has a solid green light, then the break is somewhere on the boundary wire between and the point where the guide wire is connected to the boundary wire (thick black line in the below illustration).
   
   To rectify the fault you will need boundary wire, connector(s) and coupler(s):
   a) If the suspected boundary wire is short then it is easiest to exchange all of the boundary wire between and the point where the guide wire is connected to the boundary wire (thick black line).
   b) If the suspected boundary wire is long (thick black line) then do as follows: Put and back to their original positions. Then disconnect. Connect a new loop wire to it. Connect the other end of this new loop wire at the middle of the suspected wire section.
   
   If the indicator lamp now is green, then the break is somewhere in the wire between the disconnected end to the point where the new wire is connected (thick black line below). In that case, move the connection for the new wire closer to the disconnected end (roughly at the middle of the suspected wire section) and check again if the indicator lamp is green.
   
   Continue until only a very short section of the wire remains which is the difference between a solid green light and a flashing blue light. Then follow instructions in step 5 below.
4. If indicator lamp still flashes blue in step 3 above: Put and back in their original positions. Then switch and. If indicator lamp now is lit with a solid green light then disconnect and connect a new boundary wire to. Connect the other end of this new wire at the middle of the suspected wire section. Follow the same approach as in 3a) and 3b) above.
   
   
5. When the break is found, the damaged section must be replaced with a new wire. Always use original couplers.