Loop Signal; Troubleshooting The Loop Signal - Husqvarna Automower 420 Technical Manual

6.3 Loop signal

When measuring loop signal strength, the mower should
be placed in the charging station. Use the Tools - Test -
Charging station menu function to check that the signal
strength is within the expected values. The test provides
a quick answer to if the charging station generates all
signals and the mower can detect these signals.

6.4 Troubleshooting the loop signal

Always start by checking the LED in the charging sta-
tion. This usually provides a good indication of where
troubleshooting should begin.
Table 10: Colors in the charging station's LED
Color Status
Solid green light All signals are OK
Green flash ECO mode
Blue flash Break in the boundary wire
Red flash Break in the F or N loops
Solid blue light Poor signal from boundary wire
Solid red light Faulty circuit board
In the event of faults in the charging station follow the
instructions below:
6.4.1 Solid green light
The LED in the charging station is solid green, but nei-
ther the front or rear loop sensor detects any loop signal:
1. Generate new loop signal, see 3.10 New loop
signal on page 43. The connection between
the charging station and the mower is restored.
Test run the mower and continue with step 2 if
the mower still cannot find the loop signal for
the loop.
2. Change circuit board in charging station, refer
to 5.25 Replacing the circuit board, charging
station on page 78.
6.4.2 Green flash
ECO mode is enabled in the mower and no loop sig-
nals are at present being transmitted in the loop wires.
If the mower has been removed from the charging sta-
tion manually with the display cover closed, ECO mode
may still be enabled (green flash) so that the loop
system is not transmitting any signals. To start the loop
system manually, the mower must be replaced in the
charging station and the display cover opened. See
also the Operator's Manual for more information about
ECO mode.
6. TROUBLESHOOTING 6. TROUBLESHOOTING
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