7.
ELECTRICAL SYSTEM
This chapter deals with the problems and checks connected with the electrical system.
All work can be done using a tester without having to use special equipment.
The wiring diagrams provided in this manual (see 1.3) may be useful to help you become acquainted with the
system and trace any failures more easily.
7.1
Guide to the identification of problems in the electrical system
In the following table problems connected to the malfunctioning of the electrical system are shown, with their
probable cause and the remedial action to be taken.
Any electronic connectors that do not operate correctly must always be replaced; do not try to repair them.
PROBLEM
CAUSE
REMEDY
1
Activation of the PCB protective device ...
This activation is indicated by an audio signalling device provided that the battery is installed and charged and that the connections are
not reversed
The audio signal stops when the key is returned to the OFF position (automatic restarting). Wait a few moments before returning the
key to the ON position
... When putting the battery in for the first
time, or after having reinstalled the
battery, at the moment of putting the key
in the «ON» position (with no alarm
signal)
Reversing of battery connections
Check the connections
... When putting the battery in for the first
time, or after having reinstalled the
battery, at the first attempt at starting
(position «START») and immediately
after starting (with or without alarm
signal)
Battery has been disconnected after starting
(no alarm)
Reconnect the battery, which must always
remain connec ted
Battery has not been chemically activated or
connections are loose (with alarm)
Check that the battery is charged and the
condition of wiring
Overvoltage of the battery which is not
sufficiently charged after several attempts at
starting
Recharge the battery
Wet card (with or without alarm)
Check and dry with low force warm air
... In subsequent use, when the key is
inserted in the position «ON» (with or
without alarm)
Short circuit on the earthing of equipment,
signals or safety systems (with audio signal)
Check circuits and leads
... In the «START» position, or after a few
seconds of use (with alarm)
Corroded or loose battery terminals
Check and clean
Wet card
Check and dry with low force warm air
... After a few moments use (with alarm) Poor or missing earth connection on the charge
regulator (12.5 HP)
Check the earth connections and the
regulators fixing screws
Over-voltage from malfunctioning regulator
Check the charging circuit (see 7.8)
Disconnected or faulty battery during use
Check the battery and connections
2
With the key in the «ON» position the
panel do not come on
The battery does not supply the card
Check the connection leads
Check the battery condition
Battery or card not earthed to frame
Check and put right
Activation of the PCB protective device
See paragraphs 1a and 1c
Damaged 6.3 A fuse
Replace fuse (6.3 A - delayed action type)
3
The panel lights come on, but with the
key in the «START» position the starter
motor does not turn or does so slowly
The battery is not supplying sufficient current
Recharge the battery
Battery earth connection unreliable or not fitted
on starter relay or engine
Check and switch back on
Starting not permitted (see summary
table 7.2)
Engage the parking brake: if the indicator
light does not come on, check the
corresponding microswitch (see 7.3)
Check that the blades are disengaged: if
the problem persists, check the
corresponding microswitch (see 7.3)
From serial n° 8611666: check the neutral
N position of the change (in mechanical
drive models) or the pedal (in hydrostatic
drive models), or otherwise that the relative
microswitch is working properly
Check that the starter relay is in working
order (see 7.6)
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