jcb G20, Руководство оператора

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Maintenance
Fault-Finding
135 9831/0650-3 135
If no faults is found, proceed to Step 4.
Check the sensor signals. If scope available, display Cam and
crank signals on the scope. Change the sensor as necessary.
4 Sensor signals faulty
If no fault is found, proceed to Step 5.
Check the Cam target wheel if damaged, replace with new
camshaft.
5 Sensor target wheel fault
If no faults is found raise Techweb Helpdesk call.
Table 63. TMAF Sensor
Step Trouble Action/Remedy
Disconnect the sensor, check sensor voltage supply at the
harness connector (see relevant sensor helpfile for pin num-
bers or refer to engine electrical schematic). If voltage supply
is faulty, disconnect all other sensor in turn until voltage supply
returns. Replace the faulty sensor.
1 Sensor supply voltage or cali-
bration fault
If sensor supply voltage is OK, proceed to Step 2.
Check all the hose connections for air leaks, repair as neces-
sary.
2 Air inlet fault
If no fault is found proceed to step 3.
Check the condition of sensor to harness connection, make
sure the seals are in place, check for signs of corrosion or con-
tamination. Repair/replace as necessary.
3 Sensor connection faulty
If no fault is found, proceed to Step 4.
Check the sensor resistance (see relevant help file page). If
sensor is out of specification replace.
4 Sensor failure
If no faults is found, proceed to Step 5.
Check the harness continuity and machine and engine earth
contacts. Repair/ replace as necessary.
6 Wiring fault
If no fault found, raise Techweb Helpdesk call.
Table 64. High Pressure Diagnostics
Step Trouble Action/Remedy
Check the fault of type IMV or HPV (if applicable) or pressure
sensor, repair the corresponding fault.
1 Pressure diagnostics fault
If no fault is found proceed to step 2.
Read the Diagnostic Trouble Code (DTC)
Connect the battery booster
If the DTC links to high pressure control:
Check the fuel feed circuit is in good condition.
Check the diesel fuel is present in the system.
Check there is no air bubbles or emulsion in the pipes.
Check there is enough fuel pressure in the inlet pump.
Check there are no high pressure circuit leaks.
Check the quality and type of the diesel fuel.
If the low pressure circuit is faulty, repair the low pressure cir-
cuit.
2 High pressure system fault
If no faults are found, proceed to Step 3 or 4 depending on
symptoms, replace the corresponding injectors.
Perform the `Static Injector Backleak Test'.
If the static pressure is not reached, replace the high pressure
pump.
3 Engine does not start
If the static pressure is reached, replace the corresponding in-
jectors.