instrument panel RENAULT SCENIC 2008 J84 / 2.G Gas Injection LPG 3000 Workshop Manual

17C-2
MR-372-J84-17C000$059.mif
V2
17C
GAS INJECTION
Fault finding - Introduction
1. SCOPE OF THIS DOCUMENT
This document presents the fault finding procedures applicable to all computers with the following specifications:
2. PREREQUISITES FOR FAULT FINDING
Documentation type
Fault finding procedures (this manual):
–Assisted fault finding (integrated into the diagnostic tool), Dialogys.
Wiring Diagrams:
–Visu-Schéma.
Type of diagnostic tools
–CLIP + multiplex line sensor
Special tooling required
3. REMINDERS
Procedure for Mégane 2
To carry out fault finding on the vehicle's computers, switch the ignition to fault finding mode (forced + after ignition).
Proceed as follows:
–Put the vehicle card in the card reader.
–Press and hold Start button (longer than 5 seconds) with start-up conditions not fulfilled.
–connect the diagnostic tool and perform the required operations.
To cut off the + after ignition feed, proceed as follows:
–disconnect the diagnostic tool,
–press the Start button twice briefly (less than 3 seconds),
–ensure that the + after ignition feed has been cut off by checking that the computer indicator lights on the
instrument panel have gone out.
Procedure for Logan
To run fault finding on the vehicle computers, switch on the ignition. Connect the diagnostic tool and perform the
required operations.Vehicle (s): LOGAN and MEGANE 2
Function concerned: Gas Injection
Engines: K4M 764/788/698Computer name: GAS 3000
Program No.: AB
Vdiag No.: 08/10
Special tooling required
Multimeter
Elé. 1681 Universal bornier
Note:
The left-hand and right-hand xenon bulb computers are powered when the dipped headlights are lit.
Fault finding on these computers is therefore not possible until after the ignition has been switched on in
diagnostic mode (forced + after ignition) and the dipped beam headlights have been switched on.
GAZ3000_V08_PRELI / GAZ3000_V10_PRELI
LPG 3000
Program No: AB
Vdiag No: 08/10
MR-372-J84-17C000$059.mif

17C-11
MR-372-J84-17C000$118.mif
V2
GAS INJECTION
Fault finding - System operation
LPG 3000
Program No: AB
Vdiag No: 08/10
17C
Expansion valve (CNG):
–Purpose:
–It enables the pressure of the gas from the tank to be lowered to a value which is compatible with the injection
system (injectors and temperature pressure sensor downstream from the expansion valve).
–The gas pressure is approximately 3 bar at the expansion valve outlet.
–It regulates the pressure in the injector rail to the pressure in the manifold.
Reducer (LPG):
– Purpose:
–It has the same functions as the expansion valve. Furthermore, it ensures that the fuel switches from a liquid state
to a gaseous state (the gas pressure is approximately 2 bar at the reducer output).
–Operation:
The LPG expansion valve and the CNG reducer are essential components and are composed of:
●a stage for lowering the pressure from 25 bar maximum to a pressure in line with the manifold pressure,
P
output = Pmanifold + 0.85 bars (LPG)
Poutput = Pmanifold + 1.8 bars (CNG with 100 bar of pressure in the tank)
●a pressure regulator, comprised of a system of valves, springs and diaphragms,
●a cut-off solenoid valve,
●a water heating system.
–The expansion solenoid valve
This component controls only supply of gas to the expansion valve. Controlled by the computer, the solenoid valve
allows LPG into the two stages of the expansion valve, thus supplying the LPG injectors.
2. Intersystem connections:
Connections to the other computers:
–Petrol injection computer,
–protection and switching unit
–instrument panel.

17C-15
MR-372-J84-17C000$295.mif
V2
17C
GAS INJECTION
Fault finding - Fault summary table
Tool fault Associated DTC Description
DF0032617 Engine speed inconsistency
DF0071B47 Main relay circuit
DF0131B40 Tank solenoid valve circuit
DF0141B42 Gauge supply circuit
DF0161685 Impact detected
DF0171094 LPG leak detection downstream of expansion valve
DF0180512 + after ignition feed
DF0191B05 LPG pressure sensor circuit
DF0201B45 Fuel sender switching relay circuit
DF0211B46 LPG tank solenoid valve relay circuit
DF0221B60 Computer
DF0241B43 Fuel pump cut-off relay circuit
DF026C073 Multiplex network
DF0291B20 LPG tank sender signal voltage
DF0300657 LPG tank sender supply voltage
DF0311B61 LPG pressure downstream from expansion valve
DF061C100 Multiplex network
DF0740336 TDC signal circuit
DF0800560 Battery voltage
DF0811B32 Cylinder 2 injector circuit
DF0831B00 LPG pressure sensor circuit
DF0871B34 Cylinder 4 injector circuit
DF0881B33 Cylinder 3 injector circuit
DF0921B05 Expansion valve downstream LPG pressure sensor circuit
DF0951B10 LPG temperature sensor circuit
DF0960641 Sensor supply voltage
DF0981B31 Cylinder 1 injector circuit
DF0991B49 Instrument panel indicator circuit
DF1031B41 LPG expansion valve solenoid valve circuit
LPG 3000
Program No: AB
Vdiag No: 08/10
MR-372-J84-17C000$295.mif

17C-51
MR-372-J84-17C000$413.mif
V2
GAS INJECTION
Fault finding - Interpretation of faults
LPG 3000
Program No: AB
Vdiag No: 08/10
17C
DF099
PRESENT
OR
STOREDINSTRUMENT PANEL INDICATOR LIGHT CIRCUIT
CO.0 : Open circuit or short circuit to earth
CC.1 : Short circuit to + 12 V
1.DEF : Non-compliance with emission control standards
NOTESConditions for applying the fault finding procedure to stored faults:
The fault is declared present after the engine has been started and switched to LPG
mode.
Special note:
Status ET099 LPG system faulty may help in dealing with this fault.
Check the insulation and continuity on the wires of the following multiplex connections:
For Mégane 2:
LPG computer track A1
LPG computer track A2
LPG computer track A2
For Logan:
LPG computer track C1
LPG computer track E1
LPG computer track D4track 17 of the instrument panel
track 18 of the instrument panel
track 4 of the instrument panel
track 23 of the instrument panel
track 11 of the instrument panel
track 19 of the instrument panel
Repair if necessary.
If the LPG in operation indicator light does not light up normally, carry out fault finding on the instrument
panel (see 83A, Instrument panel).
AFTER REPAIRDeal with any faults displayed by the diagnostic tool.
Clear the computer memory.
Carry out a road test followed by another check with the diagnostic tool.
GAZ3000_V08_DF099 / GAZ3000_V10_DF099