|
Fault
|
Cause
|
Test method
|
Solution
|
Notes
|
|
Own diagnosis control unit
|
If the regulator of the control unit measures a voltage of over
6V for more than 150 seconds when the ignition is switched off,
this is interpreted as a fault. A fault message is also output by
the diagnostic program if the control unit regulator measures a
voltage of less than 6 V for more than 5 seconds when the engine is
running.
|
Using a voltmeter, check that PIN 43 of the control unit is
powered from the battery negative terminal.
|
Check the current protection on the RED BLACK wire. Check the
connection of the positive wire to the voltage terminal.
Using a multimeter set to OHM, measure the
continuity of the RED BLACK conductor.
|
|
|
Gas injector nozzles
|
In gas mode, an injector shows a fault if for 10 successive
injections, open loads or short-circuits are detected at the coil
of the nozzle concerned.
|
Separate the connection of the gas injector reported as faulty,
and with a multimeter set to OHM check the resistance of the gas
injector. The correct value must be 1.1 Ohm.
|
If the gas injector is functioning, using a multimeter set to
OHM check the continuity of the wires for the power supply to the
injector reported as faulty (see "pin-out" of connection to gas
injector control unit) between the injector connection and that of
the control unit (Pin 26,27,28,54,55,56).
If a different resistance is measured, the gas
injector must be replaced.
If the cable connection is broken, where
possible repair this, otherwise replace the entire wire.
If the cable connection is functioning, replace
the injector with the letter on the associated wire which
corresponds to that of the cylinder reported by the
diagnostics.
|
|
| |
|
|
If the cable connection is functioning, replace the injector
with the letter on the associated wire which corresponds to that of
the cylinder reported by the diagnostics.
|
For Corsa-D, Meriva and Astra H: A=1, B=2, C=3, D=4
For Zafira: A=1, B=3, C=2, D=4
|
|
Low gas pressure
|
In gas mode, a fault is reported if the absolute pressure value
remains below the minimum values defined in the file (for a
duration which exceeds the value set in the program).
The fault message however is only given if at
the same time no reserve for the gas level is detected. In this
case, the system switches back to petrol mode due to lack of
fuel.
|
Connect the tester to the diagnostic connection of the control
unit. With the engine idling at minimum revs, check the operating
pressure. With the engine at minimum idle, the pressure detected at
the point "F2 - PRESSURE" must be between 1.20 bar and 1.40
bar.
Using a multimeter set to OHM check the
continuity of the wire (see "pin-out" of connection to gas injector
control unit) between the pressure sensor connection and that of
the control unit (Pin 8, 9, 37).
|
Turn the setscrew on the pressure regulator until the pressure
measured lies within the necessary range.
If no pressure is measured or if the measured
value deviates greatly from the effective value, check the p- T gas
sensor and the corresponding connections.
If the cable connection is broken, where
possible repair this, if necessary replace the entire wire.
If the cable connection is functioning, replace
the gas sensor or .
|
|
|
High pressure
|
In gas mode, a fault is reported if the differential pressure
measured exceeds 1.4 bar for 5 seconds on aspiration engines.
|
Connect the tester to the diagnostic connection of the control
unit. With the engine idling at minimum revs, check the operating
pressure. With the engine at minimum idle, the pressure detected at
the point "PRESSURE" must be between 1.20 and 1.40 bar.
|
Turn the setscrew on the pressure regulator until the pressure
measured lies within the necessary range.
|
|
|
Engine temperature separate
|
Fault in gas mode if the temperature sensor is not connected for
more than 10 seconds.
|
Using a multimeter set to OHM check the continuity of the wire
(see "pin-out" of connection to gas injector control unit) between
the temperature sensor connection and that of the control unit (Pin
33, 34).
|
If the cable connection is broken, where possible repair this,
if necessary replace the entire wire.
If the cable connection is functioning, replace
the temperature sensor .
|
|
|
Engine temperature too low
|
Fault in gas mode if for 10 seconds, a temperature value of less
than -40 °C is measured.
|
Connect the tester to the control unit diagnostic connection.
With the engine idling, check the operating temperature at "F2 -
Water temperature".
|
If the temperature given is not the actual temperature, replace
the temperature sensor .
|
|
|
Engine temperature too high
|
Fault in gas mode if for 10 seconds, a temperature value of over
175 °C is measured.
|
Connect the tester to the control unit diagnostic connection.
With the engine idling, check the operating temperature at "F2 -
Water temperature".
|
If the temperature given is not the actual temperature, replace
the temperature sensor .
|
|
|
Gas temperature too low
|
Fault in gas mode if for 10 seconds, a temperature value of less
than -40 °C is measured.
|
Connect the tester to the control unit diagnostic connection.
With the engine idling, check the operating temperature at "F2 -
Gas temperature".
|
If the temperature given is not the actual temperature, replace
the gas sensor or .
|
|
|
Gas temperature too high
|
Fault in gas mode if for 10 seconds, a temperature value of over
175 °C is measured.
|
Connect the tester to the control unit diagnostic connection.
With the engine idling, check the operating temperature at "F2 -
Gas temperature".
|
If the temperature given is not the actual temperature, replace
the gas sensor or .
|
|
|
System Solenoid Valves
|
During gas operation, short-circuits or open circuits may be
established at the coils of the gas solenoid valves. A fault is
indicated if the current consumption detected by the system (max.
approx. 3.6 A) for 5 seconds does not return to the normal
operating range.
|
Using a multimeter set to OHM check the continuity of the wire
(see "pin-out" of connection to gas injector control unit) between
the two connections on the solenoid valves on the pressure
regulator and that of the control unit (Pin 24, 52).
|
If the cable connection is broken, where possible repair this,
if necessary replace the entire wire.
|
|
| |
|
Check the two contacts of the solenoid valve coils on the
pressure regulator / multivalve for short-circuit or open circuit.
The correct value must be approx. 12Ω.
|
If the cable connection is functioning, replace the faulty
injection solenoid valve or .
|
|
|
Petrol Fuel Injectors
|
On the control unit, the isolator wires to the injectors are
checked for correct connection. Depending on the number of
cylinders, the control unit checks the load, short-circuit and open
circuit for the petrol injectors. If no signal is received within 8
seconds, a fault is indicated for the cylinder concerned.
|
Using a multimeter set to OHM check the continuity of the wires
for the power supply to the injector reported as faulty (see
"pin-out" of connection to gas injector control unit) between the
injector connection and that of the control unit (Pin 1, 2, 3, 4,
29, 30, 31, 32).
|
If the cable connection is broken, establish whether the problem
is caused by the wiring to isolate the injectors or the main
wiring. Where possible, repair this or replace the faulty
wiring.
If the cable connection is functioning, replace
the control unit or .
|
|
| |
Using the vehicle manufacturer's tester, check whether there is
a carburation fault (detected by the petrol injection control
unit). If there is a misfire, the control unit could have
interrupted the injection of fuel to one cylinder.
|
Reset the fault and check whether the fault occurs in petrol
mode. If the fault also occurs in petrol mode, carry out
diagnostics on the petrol injection.
|
|
|
|
The switch does not illuminate when the ignition key is turned
to position "II".
|
Power supply to control unit interrupted.
|
Check the power supply to the control unit.
|
Replace or repair cable.
|
|
| |
|
Check the power supply fuse.
|
Replace fuse.
|
|
| |
The injector isolator wires are not compatible with the fuel
supply signals of the petrol injectors.
|
|
Replace the fuel injector isolator wires.
|
|
| |
The direct wiring to the switch is faulty.
|
|
Replace the main wiring.
|
|
| |
The control unit of the gas injection is not programmed.
|
|
Program the control unit with a file suitable for the vehicle
type.
|
|
| |
The wiring is faulty. Using a multimeter set to OHM check the
continuity of the direct wiring of the switch (see "pin-out" of
connection to gas injector control unit) between the pressure
sensor connection and that of the control unit (Pin 47, 48, 49,
50).
|
|
If the cable connection is broken, where possible repair this,
if necessary replace the defective wire.
If the cable connection is functioning, replace
the switch.
|
|
