Page 110 of 363
JF5111.0
INJECTION
Fault finding -Aid
17
E7J 780
engine
For further details, refer to section 12
Injector resistance = 14.5 Ω
Idle regulation stepping
motor resistance : A - D = 52 Ω
B - C = 52 Ω
Canister bleed valve resistance = 35 Ω
Ignition coil resistance : Primary = 1-3 ; 2-3 = 1 Ω
1-2 = 0.5 Ω
Secondary = 10 kΩ
Oxygen sensor heating resistance = 3 to 15 Ω
Throttle potentiometer resistance : no load 1-2 = 5440 Ωfull load 1-2 = 2200 Ω
1-3 = 4500 Ω1-3 = 4460 Ω
2-3 = 2160 Ω2-3 = 5340 Ω
Flywheel signal resistance = 220 Ω
Fuel pressure = 3 bars ignition on/ 2.5 bars at idle speed
Value for: CO = 0.3 % maximum
HC = 100 ppm maximum
CO2 = 14.5 % minimum
Lambda = 0.97 < λ < 1.03
Sensor resistance
Temperature in °C 0 20 40 80 90
Air temperature sensor
Resistance in ohms7470
to
119703060
to
40451315
to
1600--
Coolant temperature sensor
Resistance in ohms6700
to
80002600
to
30001100
to
1300270
to
300200
to
215
17-62
Page 136 of 363

Connect the bornier in place of the computer and check the insulation,
continuity and that there is no interference resistance on the line:
Computer 13 B Target sensor
Computer 31 A Target sensor
Repair if necessary.
JSA051.0
INJECTION
Fault finding - Interpretation of XR25 bargraphs17
D7F 710
engine -
35 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 5 RH side illuminated or flashingFiche n° 27 side 1/2
FLYWHEEL SIGNAL CIRCUIT
XR25 aid:*25 = CO.0 =>CO or CC- line 13 or 31
*25 = CC.0 =
>CC- line 13 or 31 on the computer
*25 = In =
>sensor incorrectly connected
5
Try to illuminate BG 5RH when the starter is activated.
BG 5RH often seen to flash if *25 = dEF as its permanent illumination is very quick.
In certain cases, BG 5RH may illuminate then extinguish.
NOTES
Check the resistance of the target sensor.
Replace the sensor if necessary.*25 = CO.0
*25 = CC.0
Check the condition of the flywheel, especially if it has been removed.
The fault persists! Replace the injection computer.
IMPORTANT: The computer has probably been damaged by an electric shock.
The cause of the damage must be found before fitting a new
computer.
Check the target sensor has been correctly connected (the sensor connector must
not be inverted).
Repair if necessary.*25 = In
The fault persists! Replace the sensor.
17-91
Page 150 of 363
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
1Flywheel signal
sensor StarterIlluminated if TDC
information is 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
motorPressure gauge must
show
2.5 bars Fuel pressure,
see Workshop
Repair
Manual or
section
5Injector
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
JSA051.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
35 tracks
Carry out the actions below if the engine does not start.
Otherwise, refer to the following pages.NOTES
3
17-105
Page 152 of 363
JSA051.0
INJECTION
Fault finding - Status and parameter checks
17
D7F 710
engine -
35 tracks
Order of
operationsFunction to be
checkedAction Bargraph Display and notes Fault finding
8Power assisted
steering
pressostatTurn wheels
to full lockIlluminated when wheels
turned to full lock
DIAG 17
Carry out the actions below (engine warm, at idle speed, no consumers)
if the engine starts.
Otherwise refer to the previous pages.
NOTES
13
17-107
Page 158 of 363
Check the insulation, continuity and that there is no interference resistance on the electrical line :
Computer 13 B Flywheel signal sensor
Computer 31 A Flywheel signal sensor
Repair.
JSA051.0
INJECTION
Fault finding - Status and parameter interpretation17
D7F 710
engine -
35 tracks
AFTER REPAIRStart the status and parameter check again from the beginning.
DIAG 5
Fiche n° 27
TDC DETECTION
XR25 aid:Status BG 3LH, incorrect illumination
No fault bargraphs should be illuminated.
When the starter motor is activated.NOTES
Check the resistance of the TDC sensor.
Replace the sensor if necessary.
Check the sensor is correctly mounted.
Repair if necessary.
Check the condition of the target (if it has been removed).
Repair if necessary.
17-113
Page 174 of 363
JSA051.0
INJECTION
Fault finding - Fault charts
17
D7F 710
engine -
35 tracks
AFTER REPAIR
Chart 1
STARTING FAULTS
Only refer to this customer complaint after a complete check using the XR25.NOTES
Erase the computer memory using G0** and carry out a road test.
Check there is fuel present
(fuel gauge faulty).
Check the fuel is of the correct type.
Check the hosesCheck no hoses are pinched
(especially after a removal operation).
Disconnect the pipe connecting the canister bleed solenoid valve
to the inlet manifold.
Plug the pipe to prevent an air leak.
If there is no other effect, the canister bleed is faulty.
Check the fuel
Connect the OPTIMA 5800 station to carry out the compression
test and follow the instructions.
Connect the OPTIMA 5800 station to carry out the flywheel test
and follow the instructions.
Check the idle speed
regulation valveTap gently to release the valve.
Check the flywheel
Check the engine
compression
Check the canister bleed
17-129
Page 175 of 363
JSA051.0
INJECTION
Fault finding - Fault charts
17
D7F 710
engine -
35 tracks
AFTER REPAIR
Chart 2IDLE SPEED FAULTS
Only refer to this customer complaint after a complete check using the XR25.NOTES
Erase the computer memory using G0** and carry out a road test.
Check there is fuel present
(fuel gauge faulty).
Check the fuel is of the correct type.
Check the hosesCheck no hoses are pinched
(especially after a removal operation).
Check the oil levelUse the dipstick to check if the
oil level is too high.
Check the fuel
Check the flywheelConnect the OPTIMA 5800 station to carry out the flywheel test
and follow the instructions.
Check the idle speed
regulation valveTap gently to release the valve.
Check the manifoldCheck the condition of the manifold gaskets.
Check the injectorsCheck, after removal, that the injectors do not drip.
A
17-130
Page 178 of 363
JSA051.0
INJECTION
Fault finding - Fault charts
17
D7F 710
engine -
35 tracks
AFTER REPAIRErase the computer memory using G0** and carry out a road test.
Chart 3
CONT
Only refer to this customer complaint after a complete check using the XR25.NOTES
Check the calipers, drums and bearings are not seized.
Check that the tyres are not under-inflated.
Check the coolingCheck that cooling is not insufficient.
Check the canister bleed
Disconnect the pipe connecting the canister bleed solenoid valve
to the inlet manifold.
Plug the pipe to prevent an air leak.
If there is no other effect, the canister bleed is faulty.
Check the axle assemblies
A
Connect the OPTIMA 5800 station to carry out the flywheel test
and follow the instructions.Check the flywheel
17-133