Husqvarna 520iHT4 Workshop Manual page 33

Symptom
The warning symbol on the keypad
flashes after start. The product then
stops.
The warning symbol on the keypad
flashes after start. The green LED
comes on but the product does not
start.
The product operates but there is no
indication light on the keypad.
The product starts immediately when
the battery is installed, without use of
the user interface.
The warning symbol on the keypad
shows a red light.
Product shows red light after a new
control unit is installed.
Defective connection between the
product and the common service tool
(CST)
1235 - 001 -
Possible causes
The power trigger is pushed during
start.
Water in the main switch signal con-
nector.
Short circuit in the keypad.
Short circuit in the main switch.
The signal between the battery and
the product is defective.
Defective connection in the keypad
connector.
The keypad is broken.
Short circuit in the keypad.
Permanent error codes prevent cor-
rect operation of the product.
The control unit is broken.
The spare part comes without soft-
ware.
The common service tool (CST) is ex-
pired.
The communication cable is dam-
aged.
Recommended step
Do not push the power trigger when
you start the product.
Disassemble and dry the stop signal
connector and then assemble it.
Replace the keypad.
Replace the main switch.
Make sure that the power connectors
between the battery and the product
are not dirty or damaged.
Make sure that the small cables be-
tween connector and the control unit
are not loose or damaged.
Do a check of the keypad function in
battery diagnostic tool. Make sure
that the keypad connector is correctly
assembled, dry, not damaged and
that there is no corrosion.
Replace the keypad.
Replace the keypad.
Erase the error codes in the common
service tool (CST).
Replace the control unit.
Use the common service tool (CST)
to install software.
Connect the common service tool
(CST) to the Internet to install new
firmware.
Repair or replace the cable.
Troubleshooting - 33