Page 181 of 363
JSA051.0
INJECTION
Fault finding - Checking conformity
17
D7F 710
engine -
35 tracks
Engine cold, ignition on.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes
5 Interpretation of
normally illuminated
bargraphsCode present
No load recognition
Illuminated if immobiliser
active
+ after ignition information
received
Locking relay control effective
Illuminates after erasing the
memory to indicate that the
operation has been carried out
correctly
Computer configured for:
manual gearbox (G50*2*)
automatic transmission
(G50*1*)
1
2
3
4
5
12
12
19
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JSA051.0
INJECTION
Fault finding - Checking conformity
17
D7F 710
engine -
35 tracks
Engine cold, ignition on.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes
6 Throttle position
potentiometerNo load
# 17
Accelerator
pedal slightly
depressed
Full load
# 17 10 < X < 50
185 < X < 245
7Absolute pressure
sensor# 01
X = Local atmospheric pressure
8Coolant temperature
sensor# 02 X = Ambient temperature
± 5 °C
9Air temperature
sensor# 03 X = Ambient temperature
± 5 °C
10
Idle speed regulation
stepping motor# 12The value read is variable
depending on the coolant
temperature :
11 % ≤ X ≤ 100 %
11Engine speed
# 06 X = 0 rpm
12
Canister bleed# 23 X = 0.7 %
2
2
2
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JSA051.0
INJECTION
Fault finding - Checking conformity
17
D7F 710
engine -
35 tracks
Engine warm, at idle speed, after fan assembly has operated at least once NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes
4 Interpretation of
normally illuminated
bargraphs
-
Code present
No load recognition
Engine speed information
received
+ after ignition information
received
Locking relay control effective
Idle speed regulation active
Richness regulation active1
2
5
4
6
6
3
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Page 190 of 363
JSA052.0
INJECTION
Fault finding- Introduction
17
D7F 710
engine -
55 tracks
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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JSA052.0
INJECTION
Fault finding - Introduction
17
D7F 710
engine -
55 tracks
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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JSA052.0
INJECTION
Fault finding - Introduction
17
D7F 710
engine -
55 tracks
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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REPRESENTATION OF THE BARGRAPHS
Illuminates when a dialogue has been established with the product computer. If it remains
extinguished:
- the code does not exist,
- there is a fault in the tool, the computer or the line
REPRESENTATION OF THE FAULTS (always on a coloured background)
If illuminated, indicates a fault on the tested product, the associated text defines the fault.
If extinguished, indicates that the fault has not been found on the tested product.
REPRESENTATION OF THE STATUSES (always on a white background)
Engine off, ignition on, no operator action
The status bargraphs on the fiche are represented as the status which they should have when the engine is
off, the ignition is on and there is no operator action
- If on the fiche the bargraph is represented as
- If on the fiche the bargraph is represented as
- If on the fiche the bargraph is represented as the test kit should give as information
either or
Engine running
Extinguishes when the function or condition given on the fiche is no longer performed.
Illuminates when the function or condition given on the fiche is performed
Fiche n° 27 is a generic fiche used for several engines.
The different engines do not use all the bargraphs. To find out the bargraphs dealt with by the injection
computer, after having set up a dialogue with the computer, press the V and 9 buttons simultaneously.
The bargraphs dealt with will:
- illuminate permanently for non memorisable fault bargraphs or status bargraphs,
- flash for memorisable fault bargraphs.
To return to fault finding mode, press button D.
JSA052.0
INJECTION
Fault finding - XR25 fiche
17
D7F 710
engine -
55 tracks
the test kit should give as
information
the test kit should give as
information
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Connect the bornier in place of the computer and check the insulation and continuity of the line:
Computer 18 Earth
Computer 2 Earth
Computer 3 Earth
Computer 11 7 Diagnostic socket
Computer 38 15 Diagnostic socket
Computer 1 5 Main relay
Computer 40 2 Main relay
Computer 48 2 Fuel pump relay
Repair if necessary.
JSA052.0
INJECTION
Fault finding - Interpretation of XR25 bargraphs17
D7F 710
engine -
55 tracks
Erase the computer memory using G0**.
Try to start the engine. Switch the ignition on, then deal with the other faults.
Remember to carry out a status and parameter check.AFTER REPAIR
Bargraph 1 RH extinguishedFiche n° 27 side 1/2
XR25 CIRCUIT
XR25 aid:No connection, CO, CC-, CC+
1
This bargraph must be illuminated for fault findingNOTES
Test the XR25 on another vehicle.
Check:
- the injection, engine and passenger compartment fuses,
- the connection between the XR25 and the diagnostic socket,
- the position of the ISO selector (S8),
- the conformity of the cassette.
Repair if necessary.
Check:
- the presence of + 12 V on track 16 and earth on track 5 of the diagnostic socket,
- that the XR25 cable is in good condition.
Repair if necessary.
Check, ignition on, for 12 V on track:
- 1 on the main relay,
- 3 on the main relay,
- 1 on the fuel pump relay.
Repair if necessary.
Ignition on, check for 12 V on track 5 of the main relay:
- If there is 12 V on track 5 of the main relay: replace the fuel pump relay.
- If there is not 12 V on track 5 of the main relay: replace the main relay.
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