11
6 PROBLEMS AND SOLUTIONS
This chapter supplies some useful indications for the installer to solve some problems that could arise with this
new system.
The ECU does not communicate
• Lack of power supply to the ECU
• The communication port configured on
the PC is not correct
• The communication cable is faulty
• Turn the engine on
• Verify whether the configured COM port
is correct in UTILITIES-COMMUNICA-
TION
• Replace the communication cable
The ECU does not switch off
• The communication with the PC is still
active
• Disconnect the communication cable or
exit from the SEQUENT 24 programme
and wait till the ECU is switched off
The changeover switch does not visua-
lise the GAS level
• The changeover switch is in its petrol
position (level LEDs are switched off)
• The changeover switch does not commu-
nicate (level central LEDs are blinking)
• Changeover to gas and verify the level
visualisation.
• Verify the changeover switch harness or
replace the changeover switch. In these
cases, the cause could also be the ECU.
Therefore verify whether the ECU com-
municates with the PC interface and, if
necessary, try to replace it.
The changeover switch does not com-
municate
• The level green central LEDs and the
orange rectangular LED are blinking
• In this condition the vehicle goes on run-
ning on petrol or on gas according to the
changeover switch position. Nevertheless
there is no information on the operation
and it is therefore proper to verify the har-
ness or replace the changeover switch.
The changeover switch does not switch
on
• The changeover switch harness is cut off
• The 5A fuse is cut off
• The changeover switch fails
• The ECU does not switch on
• Verify the changeover switch harness
continuity.
• Replace the 5A fuse
• Replace the changeover switch.
• Verify the ECU operation.
The vehicle works wrongly on gas
• The injectors positives are not cut correc-
tly
• Make sure you have cut all the petrol
injectors positives
• Verify you have cut as close as possible
to the injectors.
The Petrol and GAS injectors do not
inject simultaneously (you will find it
hard to make the self-mapping)
• The injectors positives are not cut correc-
tly
• Try to start the vehicle up with the gas
injectors disconnected: if the vehicle
starts up (even running bad) then there is
a problem in the injectors positive cut.
The vehicle does not start up
• Inversion between RIGHT and LEFT har-
ness
• Verify whether the injectors are connected
correctly. If the RIGHT harness and the LEFT
harness are inverted, trying to start up, the
tension on the White/Green wire is still low.
The vehicle does not change over to
gas.
• The injectors are not driven to the
ground.
•The battery bond fails.
• Verify the connection of the B1 Pin
injectors ground wire.
• Verify the connection of the C8 Pin bat-
tery ground wire.
The ECU does not switch on or it resets
itself in the gas operation
• The connection to the battery positive is
lacking or is cut off.
• The connection to the injectors positive is
lacking or is cut off.
• Verify the connection of the A1 Pin bat-
tery positive wire.
• Verify the connection of the A7 Pin
injectors positive wire.
WHAT’S HAPPENED?
WHAT TO DO
PROBLEM
The vehicle changes over to petrol in
cut-off.
• The RPM signal is taken from the coil
negative. This signal is set to zero in cut-
off.
• Take an RPM signal different from the
coils one.
The vehicle stalls while changing over
to gas.
• The 15A fuse is cut off.
• Any of the actuators relay wires is
disconnected.
• The relay fails.
• The White/Green wire is inverted with the
White/Brown one (in this case you will
hear the relay ringing).
• Verify the 15A fuse.
• Verify the connections on the actuators
relay.
• Replace the relay.
• Verify the connection of the
White/Green and White/ Brown wires.
