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JF5111.0
INJECTION
Fault finding - Checking conformity
17
E7J 780
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Checks to be carried out during a road test.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes
6 Adaptive richness After
programming
phase
# 30
# 31 64 ≤ X ≤ 192
(average value after erasing
the memory: 128)
64 ≤ X ≤ 192
(average value after erasing
the memory: 128)
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Fault finding- Introduction
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SETTING UP DIALOGUE BETWEEN THE XR25 AND THE COMPUTER
- Connect the test kit to the diagnostic socket.
- Put the selector on S8
- Switch on the ignition.
- Enter D13 9.NJ
COMPUTER IDENTIFICATION
The computer is not identified by reading a fault code but by reading the Part Number directly from the
computer. After having set up a dialogue with the computer:
ENTER G70*7700
XXX
XXX
The Part Number will then appear on the central display in three sequences.
Each sequence is displayed for approximately two seconds. The display is repeated twice .
ERASING THE MEMORY (ignition on)
After an operation on the injection system the computer’s memory can be erased by using the code G0** .
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If the information obtained by the XR25 requires electrical continuities to be checked, connect bornier MS
1048.
Bornier MS 1048 is a 35 track base with a printed circuit on which are 35 copper coated surfaces, numbered
from 1 to 35.
Using the wiring diagrams, the tracks connecting the components to be tested can be easily identified.
IMPORTANT :
• All tests using bornier MS 1048 must be carried out with the battery disconnected.
• The bornier is only designed to operate with an ohmmeter. Under no circumstances should 12 Volts be
applied to the test points.
89024S3
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Fault finding - Introduction
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DESCRIPTION OF THE FAULT-FINDING PHASES
The process described below is to be carried out in all cases of faults.
XR25 FAULT-CHECKING
This phase is the essential starting point for any intervention on the vehicle.
There are several constraints to the treatment of the bargraphs :
- A priority in the order of treatment when several bargraphs are illuminated.
- The interpretation of a bargraph depending on whether it is constantly illuminated or flashing .
1 - Order of priority
A series of illuminated bargraphs corresponding to the sensors with the same 12 V or having the same
earth, indicates a fault in this source. These priorities are dealt with in the "NOTES" section of the
fault-finding of the bargraph concerned.
2 - Input / output fault bargraphs
a) Illuminated :
The fault is present : treat the fault following the method described in the "INTERPRETATION OF XR25
BARGRAPHS" section.
b) Flashing :
Note the bargraphs displayed on the XR25.
Erase the memory of the computer and attempt to re-illuminate the bargraph: ignition on, idle speed
(or at starter speed) or by means of a road test (the "NOTES" section in the fault finding for the
bargraph concerned may help to determine the conditions under which the bargraph will illuminate).
If the bargraph has re-illuminated (fixed or flashing) :
The fault is present once again. In this case, treat the fault bargraph.
If the bargraph has not re-illuminated, check :
- the electrical lines which correspond to the flashing fault,
- the connectors of these lines (for rust, bent pins...).
- the resistance of the component found to be faulty.
- the cleanliness of the wires (insulation melted or cut, friction..).
NOTE : If the customer complaint does not correspond to the fault bargraph which is flashing
(example : Air temperature sensor fault bargraph flashing, but no customer complaint) ignore
this memorised fault and erase it.
3 - No bargraphs illuminated
If no bargraphs are illuminated on the XR25, carry out a status and parameter check. This may help in
detecting a problem.
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XR25 CHECKING STATUSES AND PARAMETERS
The status and parameter check is aimed at checking the statuses and parameters which do not illuminate
any fault bargraphs if they are outside of permitted tolerance values . This phase allows :
- Faults to be found without the illumination of fault bargraphs which may correspond to a customer
complaint (example : absence of no load information causing an unstable idle speed).
- The correct operation of the injection to be checked and the risk of faults appearing shortly after the
repair to be eliminated.
This section contains fault-finding for statuses and parameters, under their test conditions
(example : fault finding for # 01 ignition on and fault finding for # 01 engine running).
If a status does not operate normally or a parameter is outside of permitted tolerance values, consult the
fault-finding page indicated in the "Fault-finding" column.
XR25 CHECK CORRECT
If the XR25 check is correct, but the customer complaint persists, the problem must be dealt with through
customer complaints.
Treatment of customer complaints
This section has fault charts, which suggest a series of possible causes of the problem.
These lines of enquiry must only be used in the following cases :
- No fault bargraph appears on the XR25.
- No faults are detected during the checking of statuses and parameters.
- The vehicle is not operating correctly
POST-REPAIR CHECK
This operation is a simple check of the repair (by a command, or by an XR25 command mode ...).
This makes it possible to check that the system upon which the intervention has been carried out is correct
electrically.
It is an introduction to the road test.
ROAD TEST
A road test is essential in order to guarantee the correct operation of the vehicle and to test the quality of the
repair. Its role is to make sure that no faults occur (or will occur) when driving.
In order to be significant, the road test is subject to special driving conditions.
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Driving conditions for programming the adaptive variables:
During the road test, the engine speed must be stabilised for a few moments between:
260 < # 01 < 385 mbars
then 385 < # 01 < 510 mbars
then 510 < # 01 < 635 mbars
then is 635 < # 01 < 760 mbars
then 760 < # 01 < 970 mbars
Do not exceed an engine speed of 4400 rpm
The engine must be warm (coolant temperature > 75 °C).
For this test, start from a fairly low engine speed, in 3rd or 4th gear, and apply progressive acceleration to
stabilise at the pressure required for 10 seconds in each zone.
The test must then be continued by driving normally, in a varied manner for 3 to 6 miles (5 to 10 km).
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PRESENTATION OF XR25 FICHE N° 27 SIDE 1/2
FI21727-1
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PRESENTATION OF FICHE XR25 N° 27 SIDE 2/2
FI21727-2
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