Repair instructions
Group 30: Electrical system
28
Rail pressure measurement
This measurement is used for measuring the rail pres-
sure. For example if the engine doesn’t start this mea-
surement can show the rail pressure while the engine
is cranking. If it is air in the system the rail pressure
could be too low for the engine control unit to activate
injection.
1.
NOTE!
Starter key in position 0.
2.
Undo the connector from the sensor.
3.
Connect adapter cable (885675) between the sen-
sor and the engine control unit.
4.
Use multimeter (9812519) for voltage measure-
ment. Connect the COM from the multimeter to
measurement point 1. Connect V from the multim-
eter to measurement point 2.
5.
NOTE!
Starter key in position I. The multimeter
should now show 0.5 Volt which is equal to 0Mpa
(0bar).
6.
When cranking the engine, read the voltage value
on the multimeter and look in the table which pres-
sure the voltage equals.
NOTE!
To activate injection a rail pressure of at least
25 MPa (250 bar) is demanded.
Voltage
0.5
0.95
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
MPa
0
20.3
22.5
27.0
31.5
36.0
40.5
45.0
49.5
54.0
Bar
0
203.0
225.0
270.0
315.0
360.0
405.0
450.0
495.0
540.0
Voltage
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
MPa
58.5
63.0
67.5
72.0
76.5
81.0
85.5
90.0
94.5
99.0
Bar
585.0
630.0
675.0
720.0
765.0
810.0
855.0
900.0
945.0
990.0
Voltage
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
MPa
103.5
108.0
112.5
117.0
121.5
126.0
130.5
135.0
139.5
144.0
Bar
1035.0
1080.0
1125.0
1170.0
1215.0
1260.0
1305.0
1350.0
1395.0
1440.0
Voltage
3.8
3.9
4.0
4.1
4.2
4.3
4.4
4.5
MPa
148.5
153.0
157.5
162.0
166.5
171.0
175.5
180.0
Bar
1485.0
1530.0
1575.0
1620.0
1665.0
1710.0
1755.0
1800.0
