Page 21 of 363

DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIRErase the computer memory (G0**), switch the ignition off, then carry out a road
test.
Finish the operation by checking using the XR25.
1.dEF
This fault indicates that the advance corrector is seized, the injection pump has been incorrectly set or
there is a fuel supply fault.
It is taken into account when the advance noted by the needle lift sensor differs by more than 5° from the
advance value requested by the computer.
NOTE : If there is a fault where the advance corrector is seized, there will be a characteristic noise when
the ignition is switched on (irregular clicking of the corrector).
The fault is present if the bargraph is illuminated when the engine is
running.NOTES
6
CONT
- Check the condition of the fuel supply to the pump and the injectors (filter blocked, pipe kinked, air
leak, ...).
Check the type of diesel fuel used in extreme cold weather (a "summer " type diesel fuel may cause
this fault at -15 °C).
- Check the pump timing and check the tightness of the pump pulley.
- If the fuel supply and the pump timing are correct, replace the advance corrector.
13-17
Page 23 of 363

DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIRErase the computer memory (G0**), switch the ignition off, then carry out a road
test.
Finish the operation by checking using the XR25.
Bargraph 7 RH illuminated (co.0) or flashing (cc.1)
EGR solenoid valve circuit
XR25 aid:*27 :co.0 : Open circuit or short circuit to earth
cc.1 : Short circuit to 12 volts
7
Use bornier Elé. 1332 for any operations on the computer connector.NOTES
Fiche n° 60 1/2
co.0
Measure the resistance of the EGR solenoid valve at its connector. Replace the EGR solenoid valve if the
resistance is not approximately 45 ohms.
Ensure continuity of the connection between track 5 on the computer connector and track 1 of the EGR
solenoid valve connector.
Ensure the presence of + after ignition feed on track 2 of the EGR solenoid valve connector, wiring side.
Ensure the insulation from earth of the connection between track 5 on the computer connector and track 1
of the EGR solenoid valve connector.
Test the connections on the 2 connectors.
None NOTES
If the fault persists after these tests, replace the EGR solenoid valve.
If the "EGR solenoid valve circuit" fault reappears, replace the computer (consult the "Aid" section for this
operation).
cc.1
Measure the resistance of the EGR solenoid valve at its connector. Replace the EGR solenoid valve if the
resistance is not approximately 45 ohms.
Ensure insulation in relation to +12 volts of the connection between track 5 on the computer connector and
track 2 of the EGR solenoid valve connector.
Even if present at the moment of testing, this fault is still declared
by a flashing BG 7RH side. To confirm its presence and the necessity
of following the fault finding below, start the engine.
The fault is present if the bargraph illuminates when the engine is
running.
NOTES
If the fault persists after these tests, replace the EGR solenoid valve.
If the "EGR solenoid valve circuit" fault reappears, replace the computer (consult the "Aid" section for this
operation).
13-19
Page 25 of 363

DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIRErase the computer memory (G0**), switch the ignition off, then carry out a road
test.
Finish the operation by checking using the XR25.
Bargraph 9 RH illuminated (co.0) or flashing (cc.1)
PAS pump assembly relay control circuit
XR25 aid:*29 :co.0 : Open circuit or short circuit to earth
cc.1 : Short circuit to 12 volts
9
Use bornier Elé. 1332 for any operations on the computer connector.NOTES
co.0
Measure the resistance of the PAS pump assembly relay coil (position C on the engine connection unit).
Replace the relay if its resistance is not approximately 65 ohms.
Ensure the continuity and insulation from earth of the connection between track 20 on the computer
connector and terminal 2 on the pump assembly relay mounting.
Ensure the presence of + after ignition feed at terminal 1 of the pump assembly relay mounting.
Check the connections on the computer connector and the relay mounting.
None NOTES
If the fault persists after these tests, replace the PAS pump assembly relay.
If the "PAS pump assembly relay control circuit" fault reappears, replace the injection computer (consult
the "Aid" section for this operation).
cc.1
Measure the resistance of the PAS pump assembly relay coil (position C on the engine connection unit).
Replace the relay if its resistance is not approximately 65 ohms.
Ensure the insulation from + 12 Volts of the connection between track 20 of the computer connector
and terminal 2 on the pump assembly relay mounting.
Even if present at the moment of testing, this fault is still declared
by a flashing BG 9RH side. To confirm its presence and the necessity
of following the fault finding below, erase the computer memory
then start command mode G36*.
The fault is present if the bargraph flashes again.
NOTES
If the fault persists after these tests, replace the PAS pump assembly relay.
If the "PAS pump assembly relay control circuit" fault reappears, replace the injection computer (consult
the "Aid" section for this operation).
Fiche n° 60 1/2
13-21
Page 29 of 363
DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIRErase the computer memory (G0**), switch the ignition off, then carry out a road
test.
Finish the operation by checking using the XR25.
Bargraph 12 RH illuminated
Full load or no load not programmed12
None NOTES
Programme the full load position of the accelerator pedal using command G31* (do not adjust the load
lever directly).
Enter code G31* on the XR25 (engine speed zero).
- Press the accelerator pedal when the display flashes "PF".
The display then shows "bon", "Fin" then "6/7.dIE" when the procedure has been completed correct-
ly. Bargraph 12 RH side must be extinguished.
- Switch off the ignition.
Fiche n° 60 1/2
13-25
Page 30 of 363

DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIRErase the computer memory (G0**), switch the ignition off, then carry out a road
test.
Finish the operation by checking using the XR25.
Bargraph 13 LH flashing (cc.1)
Air conditioning cut out information circuit
XR25 aid:*13 :cc.1 : Short circuit to 12 volts
13
None NOTES
Fiche n° 60 1/2
cc.1
Ensure insulation in relation to 12 volts of the connection between track 19 on the computer connector
and track 18 on the air conditioning computer connector.
Test the connections on the 2 connectors (+ intermediate connection engine / dashboard).
Even if present at the moment of testing, this fault is still declared
by a flashing BG 13LH side. To confirm its presence and the necessity
of following the fault finding below, erase the computer memory
then start the engine. The fault is present if the bargraph flashes
when the engine is running.
NOTES
If the fault persists after these tests, replace the air conditioning control module.
If the "air conditioning cut out information "fault reappears, replace the diesel injection computer (consult
the "Aid" section for this operation).
13-26
Page 32 of 363

Bargraphs 9 RH and 9 LH side
Air conditioning
XR25 aid :BG 9LH illuminated if AC requested
BG 9RH illuminated if AC authorised
DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIR
Bargraphs 5 and 6 RH and LH sides
Relay control5
None NOTES
These bargraphs visualise the control of the various relays:
- Preheating relay N° 1.
- Preheating relay N° 2 (not used).
- Power assisted steering pump assembly relay (for AC + PAS).
- Altimetric corrector relay.
Fiche n° 60 2/2
6
Ensure the bargraphs operate correctly
9Fiche n° 60 2/2
If
BG 9LH is extinguished when AC is requested, ensure the continuity and insula-
tion of the connection between track 11 of the diesel computer connector and
track 20 of the AC computer connector.
NOTES
Bargraph 10 LH side
Warning light control
XR25 aid :BG 10LH is illuminated if the warning light on the instrument panel
is controlled. This bargraph is normally illuminated; it extinguishes
when the engine is running if there is no fault.
10Fiche n° 60 2/2
None
NOTES
13-28
Page 33 of 363
DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Interpretation of XR25 bargraphs13
AFTER REPAIREnsure the bargraphs operate correctly
Bargraph 10 RH side
Preheating warning light control
XR25 aid :BG 10RH illuminated during the preheating phase
10Fiche n° 60 2/2
None
NOTES
Fiche n° 60 2/2
Bargraph 11 LH side
Load information output
XR25 aid :This bargraph allows visualisation of the emission of the load lever
position information (this information is not used for this applica-
tion). It is permanently illuminated.
11Fiche n° 60 2/2
None
NOTES
Bargraph 11 RH side
Engine speed information output
XR25 aid :This bargraph allows visualisation of the emission of engine speed
information (this information is not used for this application). It is
permanently illuminated.
11Fiche n° 60 2/2
None NOTES
13-29
Page 35 of 363

DPCF01 1.0
LUCAS DIESEL INJECTION
Fault finding - Aid
13
REPLACING THE COMPUTER
A)On these computers it is necessary to programme the load lever full load position (this value is required to
replace and adjust the load lever position potentiometer).
Programming procedure:
• Enter code G31* on the XR25 (engine speed zero)
• Press the accelerator pedal until the display flashes
"PF".
The display then shows "bon", "Fin" then "6/7.dlE" when the procedure has been carried out correctly.
Bargraph 12 RH side must be extinguished.
• Switch off the ignition.
B)Lucas digital DPC injection computers are sold pre-configured to "with air conditioning".
If the vehicle does not have air conditioning, use command G50*4* on the XR25 to programme "without
air conditioning".
Lucas digital DPC injection computers are sold pre-configured to "with power assisted steering" (with po-
wer assisted steering pump assembly).
If the vehicle does not have a power assisted steering pump assembly (vehicle without air conditioning),
use command G50*9* on the XR25 to programme "without power assisted steering".
Vehicles fitted with power assisted steering but without air conditioning must be configured to "without
power assisted steering".
REPLACING THE LOAD LEVER POSITION POTENTIOMETER
The load lever position potentiometer may only be replaced in After Sales if the full load position has been
programmed into the computer before the fault with the potentiometer.
Procedure for replacing and adjusting the load lever position potentiometer:
• Fit the new potentiometer into position without locking the mounting bolts.
• Connect the potentiometer and set up the XR25 (S8 code D34).
• Start command G32* on the XR25, keep the accelerator pedal fully depressed (do not touch the load lever
directly) and turn the potentiometer until the display on the XR25 shows a value other than H.L (outside li-
mits). Adjust the setting by turning the potentiometer to obtain 0 on the display.
• Tighten the mounting bolts with the potentiometer in this position then press * to complete the adjus-
tment procedure.
13-31