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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Carry out the actions below if the engine does not start.
Otherwise, refer to the following pages.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Flywheel signal
sensorStarterIlluminated if TDC
information detected
DIAG 5
2Fuel pump
G10*Fuel pump should be
heard to operateDIAG 6
3 IgnitionConnect
Optima
StationStarting test, complete
guide on Optima StationUse Optima
5800 Station
4Fuel pressureConnect
pressure
gauge to
fuel inlet
and activate
starter
motorThe pressure gauge must
show 2.5 bars Fuel pressure,
see Workshop
Repair
Manual or
section
5Injection
commandStarterFuel must come out of
the injector
DIAG 11
6Engine
compressionConnect
Optima
StationComplete guide on
Optima StationUse Optima
5800 Station
7 FlywheelConnect
Optima
StationOscilloscope.
Complete guide on
Optima StationUse Optima
5800 Station
3
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Charging
circuit# 0413 < X < 14.5 V
DIAG 1
2Throttle
potentiometerNo loadIlluminated(does not
flash!)DIAG 2
3Idle speed
regulation# 06
# 12
# 21690 < X < 790 rpm
4 % < X < 14 %
- 4.3 % < X < 3.9 %DIAG 7
4Anti-pinking
circuit# 13 (at
3500 rpm,
no load)X variable and not zeroDIAG 8
5 Pressure circuit# 01
# 16270 ≤ X ≤ 430 V
X = atmospheric pressureDIAG 9
6Richness
regulation# 35
# 050 < X < 255
X varies around 128
50 ≤ X ≤ 900 V
DIAG 10
See also DIAG
15
7 Fuel pressureConnect a
pressure
gauge to the
fuel gallery
and activate
the starter
motorPressure gauge must
show
2.5 bars Fuel pressure,
see Workshop
Repair
Manual or
section
Carry out the actions below (engine warm, at idle speed, no consumers)
if the engine starts.
Otherwise refer to the previous pages.
NOTES
6
6
2
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
8Air
conditioningAC selected
# 06
# 44
# 06
# 44Extinguished if fast idle is
not active
Illuminated if the air
conditioning requests
compressor operation
Illuminated if the
injection authorises
compressor operation
690 ≤ X ≤ 790 rpm
300 ≤ X ≤ 4000 W
800 ≤ X ≤ 900 rpm
300 ≤ X ≤ 4000 W
DIAG 16
9Power assisted
steering
prestostatTurn wheels
to full lockIlluminated when wheels
turned to full lockDIAG 18
Carry out the actions below (engine warm, at idle speed, no consumers)
if the engine starts.
Otherwise refer to the previous pages.
NOTES
10
10
9
13
10
9
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JSA052.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
55 tracks
Check during road test.NOTES
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Vehicle speed
information# 18X = speed read on the
speedometer in km/h
DIAG 13
2Adaptive
richnessProgramm-
ing
# 30
# 31106 ≤ X ≤ 150
106 ≤ X ≤ 150 DIAG 14
3Emission of
pollutants2500rpm
after driving
At idle
speed, wait
for
stabilisationCO < 0.3 %
CO2 > 13.5 %
O2 < 0.8 %
HC < 100 ppm
0.97 < λ < 1.03
CO < 0.5 %
HC < 100 ppm
0.97 < λ < 1.03
DIAG 15
see also
DIAG 10
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JSA052.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
55 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 1BATTERY VOLTAGEFiche n° 27
XR25 aid: Battery voltage ignition on, Minimum< # 04 < Maximum
Battery voltage idle speed, Minimum< # 04 < Maximum
No fault bargraphs should be illuminated.
No consumersNOTES
If # 04 < Minimum, the battery is discharged:
Check the charging circuit to determine the cause of this fault.
Ignition on
If # 04 > Maximum, the battery may be overcharged:
Check the charging voltage is correct with and without consumers.
If # 04 < Minimum, the charging voltage is too low:
Check the charging circuit to determine the cause of this fault.
At idle speed
If # 04 > Maximum, the charging voltage is too high:
The alternator regulator is faulty. Repair this fault and check the electrolyte level in the battery.
NOTE:
The battery and the charging circuit may be checked using the OPTIMA 5800 station (measurement does
not require the battery to be disconnected, which retains the memories of the computers).
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Check the insulation and the continuity of the line:
Computer 19 C Throttle potentiometer
Computer 45 B Throttle potentiometer
Computer 46 A Throttle potentiometer
Repair if necessary.
JSA052.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
55 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 2THROTTLE POTENTIOMETERFiche n° 27
XR25 aid:# 17 outside tolerances
# 17 does not vary when throttle moves
Status BG 2LH or 2RH, incorrect illumination
No fault bargraphs should be illuminated.
Ignition on or engine running.NOTES
Status bargraph 2RH
incorrect illuminationNoneNOTES
Check the resistance of the throttle potentiometer.
Replace the throttle potentiometer if necessary.
# 17 is fixedNoneNOTES
Check the resistance of the throttle potentiometer when the throttle is activated.
If the resistance varies, check the electrical lines of the sensor.
If the resistance does not vary, check that the sensor is connected mechanically to the throttle.
If necessary, replace the sensor.
# 17 outside tolerancesNoneNOTES
Check the upper and lower stops of the throttle.
Check the accelerator control (points of resistance and friction).
Repair.
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Check the insulation, continuity and that there is no interference resistance on the electrical line :
Computer 15 2 Coolant temperature sensor
Computer 44 1 Coolant temperature sensor
Repair.
JSA052.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
55 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 3COOLANT TEMPERATURE
XR25 aid:# 02 = Engine temperature ± 5 °C
No fault bargraphs should be illuminated.
NOTES
If the value read is inconsistent, check the sensor correctly follows the standard table of values for
"resistance as a function of temperature".
Replace the sensor if the values are incorrect (
NOTE : If a sensor is incorrect, this is often due to an electric
shock).
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Check the insulation, continuity and that there is no interference resistance on the electrical line :
Computer 20 2 Air temperature sensor
Computer 46 1 Air temperature sensor
Repair.
JSA052.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
55 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 4AIR TEMPERATUREFiche n° 27
XR25 aid:# 03 = Temperature under the bonnet ± 5 °C
No fault bargraphs should be illuminated.
NOTES
If the value read is incoherent, check the sensor correctly follows the standard table of values for
"resistance as a function of temperature".
Replace the sensor if the values are incorrect (
NOTE : If a sensor is incorrect, this is often due to an electric
shock).
17-184