trip computer RENAULT SCENIC 2009 J84 / 2.G Engine And Peripherals EDC16 Workshop Manual

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DIESEL INJECTION
Fault finding – System operation13B
13B - 14V3 MR-372-J84-13B250$135.mif
EDC16
PROGRAM No: C1
Vdiag No.: 51
Exhaust gas recirculation management
The exhaust gas recirculation system comprises a direct current EGR valve controlled by an H bridge in the
computer. This system has a built-in valve position feedback potentiometer.
The EGR valve is controlled in a closed loop on the change in the air flow measured by the flow sensor.
The potentiometer is used in the fault finding procedure for the EGR valve position.
Warning light management:
Instrument panel display
The computer manages the data display on the instrument panel relating to engine operation. This involves six
functions:
–the pre-postheating warning light,
–the coolant temperature warning light or warning message;
–the fault level 1 warning light (non-critical fault),
–the fault level 2 warning light (emergency stop),
–the OBD warning light (European On Board Diagnostic).
These five functions are represented by 4 or 5 warning lights and/or messages sent by the trip computer.
A 3 second visual inspection is carried out by the injection computer when ignition is switched on (automatic
procedure for test managed by the instrument panel).
Orange Pre-post heating/non-critical fault SERVICE warning light (level 1)
This light is used both as an in-operation indicator light and as a system fault indicator:
–Continuously lit with + after ignition feed:
Indicates preheating of the spark plugs.
–Continuous lighting accompanied by the message CHECK INJECTION or ELECTRONIC FAULT:
Indicates a level 1 fault (implies operation in injection system defect mode).
The driver should carry out repairs as soon as possible.
Temperature warning light/red EMERGENCY STOP (level 2)
This indicator light is used both as an in-operation indicator light and as a system fault warning light. Lights up for
3 seconds when the ignition is switched on (automatic test procedure managed by the instrument panel):
–Continuously lit or alternately lit with ENGINE OVERHEATING message:
Indicates engine overheating (the driver is free to choose whether or not to stop the vehicle).
–Continuously lit with the FAULTY INJECTION message:
Indicates a level 2 fault (In this case, the injection is automatically cut after a few seconds).
The driver should carry out repairs as soon as possible.
ORANGE OBD excess pollution warning light
An engine symbol accompanied by the message CHECK EMISSION CONTROL.
This warning light comes on if the system has one or more OBD faults.
This warning light is used to warn the driver of injection faults leading to excessive pollution or that the EOBD* system
has been deactivated.
The injection computer requests activation of the OBD warning light for a present fault only after three successive
driving cycles.
A 3 second visual inspection is carried out by the injection computer when ignition is switched on (automatic
procedure for test managed by the instrument panel).
*EOBD: Electronic on board diagnostics.

Page 16 of 273

DIESEL INJECTION
Fault finding – System operation13B
13B - 16V3 MR-372-J84-13B250$135.mif
EDC16
PROGRAM No: C1
Vdiag No.: 51
3. Conditions for clearing an OBD fault
An OBD fault is cleared in several steps.
The fault present in the diagnostic tool is not stored (following repair) until after 3 trips with the vehicle.
The OBD warning light will only light up after these 3 driving cycles.
The warning light coming on does not always mean that there is a fault on the system.
In order that the OBD fault and the display parameters are cleared from the computer, the system needs to
go through 40 engine heating cycles.
An engine heating cycle is a driving cycle during which:
–the engine coolant temperature reaches at least 71.1 ˚C,
–the engine coolant temperature varies by 22.2 °C in relation to the engine starting temperature.
If one of these conditions is not fulfilled, the OBD fault will still be present or stored in the injection computer.