Fault Location Tree

ALP 1 NO COMMUNICATION WITH ECU VIA XR25 TOOL

INSTRUCTIONS Use test connector block Elé. 1332 for any work at the ECU connector.

Make sure the XR25 tool is not the cause of the fault by trying to communicate with an ECU on another vehicle. If the XR25 tool is not at fault and communication fails with every other ECU on the same vehicle, a faulty ECU may be disrupting the K and L diagnostic lines. Disconnect components one at a time to locate this ECU. Check that the ISO interface is in position S8, that you are using the latest XR25 cassette version and the correct access code (D34). Check the battery voltage and carry out the necessary work to obtain a correct voltage (battery voltage > 10.5 volts).

Check that the 15 ampere fuses in the engine interconnection box are not blown (positions 3 and 4). Check the connection and condition of the connectors at the ECU connector and the engine / dashboard connection R67. Check that the ECU is correctly supplied: Ground on pin 2 of the ECU connector (check the condition and tightness of the GMP ground strap and the engine ground on the gearbox casing). + APC on pin 1 of the ECU connector.

Check that the diagnostic socket is correctly powered: Earth on pin 5. + AVC on pin 16. Check and ensure continuity and isolation of the lines of the diagnostic socket / ECU link: Between pin 10 of the ECU connector and pin 15 of the diagnostic socket. Between pin 13 of the ECU connector and pin 7 of the diagnostic socket.

If communication still fails after these checks, replace the ECU (see the "help" chapter for this procedure).

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.

Clear any bar graph faults that are displayed.

ALP 2 IDLE SPEED TOO HIGH, AIR CONDITIONING REQUESTED

INSTRUCTIONS Only consult this customer complaint after a full check with the XR25 tool.

This fault may be related to fast idle operation.

Check the condition of the pneumatic circuit of the fast idle solenoid valve.

Check the wire between pin 11 of the injection ECU and pin 20 of the air conditioning ECU connector BE ("A/C Inj. / fast idle" signal) for a short to +12 volts.

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.

ALP 3 NO FAST IDLE WITH AIR CONDITIONING REQUESTED

INSTRUCTIONS Only consult this customer complaint after a full check with the XR25 tool.

Check the wire between pin 11 of the injection ECU and pin 20 of the air conditioning ECU connector BE ("A/C Inj. / fast idle" signal) for an open circuit or a short to ground.

This fault prevents the left bar graph 9 "air conditioning requested" from lighting up.

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.

ALP 4 Starting problem with no fault warning light (no start or hard starting)

INSTRUCTIONS Only consult this customer complaint after a full check with the XR25 tool.

If the XR25 tool reports no fault, make sure the problem is not caused by an immobilizer system fault.

Check glow plug operation: activate command mode G10*1* and check for voltage at the glow plugs. If the glow plugs are not powered, check the 3-way connector on the relay box and the condition of the 70 A fuse on the engine interconnection box.

If the problem persists, check the fuel supply circuits (pump and injectors). If necessary, carry out a full engine check (starter motor cranking speed, pump timing, injector condition, valve clearances, compressions, etc.).

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.

ALP 5 FAULT WARNING LIGHT ON WITH NO FAULT SHOWN BY XR25 TOOL

INSTRUCTIONS Only consult this customer complaint after a full check with the XR25 tool.

If the XR25 tool reports no fault, check the glow plug supply wiring for a short to ground, or check for a short-circuited glow plug(s).

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.

ALP 6 VEHICLE EMITS BLACK SMOKE AT ALTITUDE

INSTRUCTIONS Only consult this customer complaint after a full check with the XR25 tool.

Measure the altitude corrector resistance at the 10-way pump connector (between pins 1 and 6).

Replace the altitude corrector if the resistance is not approximately 15 ohms.

Check continuity of the wire between pin 1 of the pump connector on the wiring side and pin 5 of the altitude corrector control relay socket (position H of the relay board in the engine interconnection box).

Make sure there is a ground on pin 6 of the pump connector on the wiring side.

AFTER REPAIR Carry out a road test, then a check with the XR25 tool.