[4] Check component Y74 (Pressure control valve).: Signal line is interrupted.

[4] Check component Y74 (Pressure control valve).: Signal line is interrupted.

Test 1: Check component Y74 (Pressure control valve).

1. Check component Y74 (Pressure control valve).

Test 1.1: Inspect component Y74 (Pressure control valve) for leaks.

Test 1.2: Read actual value of component Y74 (Pressure control valve).

Test 1.3: Test signal voltage of component Y74 (Pressure control valve).

Test 1.4: Test current consumption of component Y74 (Pressure control valve).

Test 1.5: Check internal resistance of component Y74 (Pressure control valve).

1.1. Inspect component Y74 (Pressure control valve) for leaks.
Inspect component Y74 (Pressure control valve) for leaks.
Figure legend

- [A]Leak oil line connection on return line
- 054Leak oil line
- 055Connect the shop-made fuel line to the connection fitting on the rail and hold it in the measuring cup.
- 057Measuring beaker1Liters
- 117Matra clamp
Test prerequisites:

- Clamp off fuel return line with matra clamp.
- Detach leak oil line at rail connecting pipe, attach fuel hose to line and hold in measuring cup.
- Connect the shop-made fuel line to the connection fitting on the rail and hold it in the measuring cup.
Important note:Perform the test with two people.Continue with button F2







Explanation of the following testThe rail pressure is increased to 1400 bar, allowing the leakage of component Y74 (Pressure control valve) to be detected.Whereas fuel may be running out of the fuel hose during the first 30 s, component Y74 (Pressure control valve) must be leakage free after this period.A fault is present even if only a few drops of fuel emerge from the line connected to connection fitting A during the test.Start engine.Communication with ECU required

1.2. Read actual value of component Y74 (Pressure control valve).
Test prerequisite

- Operate engine at idling speed.
- Fuel temp. of > 20°
- Carry out the test within 30 s.
Status of relevant actual value:
- Pressure control valve:Warning! Communication with ECU required.

- Fuel temperature:Warning! Communication with ECU required.
Specified value

- On/off ratio:<30%
- Fuel temp. of > 20°
Question

- Is the actual value o.k.?


YES
The actual value is okay.Possible cause and remedy

- In the event of stored faults with a high fault frequency count or in the event of customer complaints, check lines and connectors for loose contact and corrosion..
End of test

NO
The actual value is not o.k.Possible cause and remedy

- Test signal voltage of component Y74 (Pressure control valve).


1.3. Test signal voltage of component Y74 (Pressure control valve).
Figure legend

- a Adapter cable
- Y74 (Pressure control valve)
Special tool

- Adapter cable220 589 00 99 35
Test prerequisite

- Operate engine at idling speed.
- Fuel temp. of > 20°
- Carry out the test within 30 s.
Test sequence

- Switch off ignition.
- Detach coupling at component Y74 (Pressure control valve).
- Connect adapter cable between Y74 (Pressure control valve) and engine wiring harness.
- Measure direct voltage with multimeter between sockets 1 and 2
Specified value

- Voltage[1,7...2,0] V
Question

- Is the measurement value OK?







YES
The measurement value is not OK.Possible cause and remedy

- Test current consumption of component Y74 (Pressure control valve).
End of test

NO
The measurement value is OK.Possible cause and remedy

- In the event of stored faults with a high fault frequency count or in the event of customer complaints, check lines and connectors for loose contact and corrosion..
End of test

1.4. Test current consumption of component Y74 (Pressure control valve).
Figure legend

- 003Multimeter
- a Adapter cable
- Y74 (Pressure control valve)
Special tool

- Adapter cable220 589 00 99 35
Test sequence

- Switch off ignition.
- Detach coupling at component Y74 (Pressure control valve).
- Connect adapter cable between Y74 (Pressure control valve) and engine wiring harness.
- Connect multimeter as specified in connection diagram (right-hand figure).
- Operate engine at idling speed.
- Measure direct current with multimeter between sockets 1 and 2
Specified value

- Current[650...700] mA ca.4sec.
Question

- Is the measurement value OK?







YES
The measurement value is OK.Possible cause and remedy

- In the event of stored faults with a high fault frequency count or in the event of customer complaints, check lines and connectors for loose contact and corrosion..
End of test

NO
The measurement value is not OK.Possible cause and remedy

- Check internal resistance of component Y74 (Pressure control valve).
End of test

1.5. Check internal resistance of component Y74 (Pressure control valve).
Figure legend

- Adapter cable
- Y74 (Pressure control valve)
Special tool

- Adapter cable220 589 00 99 35
Test sequence

- Switch off ignition.
- Detach coupling at component Y74 (Pressure control valve).
- Connect adapter cable no. 220 589 00 99 35 at component Y74 (Pressure control valve).
- Measure resistance with multimeter between sockets 1 and 2
Specified value

- Resistor[4 ... 5]ohms
Question

- Is the measurement value OK?







YES
The measurement value is OK.Possible cause and remedy

- In the event of stored faults with a high fault frequency count or in the event of customer complaints, check lines and connectors for loose contact and corrosion..
- Test wiring from component N3/9 (CDI control unit) to component Y74 (Pressure control valve) with an ohmmeter for short circuit (positive or negative) and repair, if necessary.
End of test

NO
The measurement value is not OK.Possible cause and remedy

- Replace component Rail.
In the case of warranty or goodwill operations, see TIPS document in design group 07.16End of test