Oil Pressure Sender: Testing and Inspection

Oil Pressure and Oil Pressure Switch, Checking

Special tools, testers and auxiliary items required

• Oil Pressure Gauge (V.A.G 1342)

• Adapter (V.A.G 1342/14)

• Voltage Tester (V.A.G 1527 B)

• Connector Test Set (V.A.G 1594 C)

• Socket 24 mm and Jointed Extension (T40175)

• For the functional check and servicing of the optical and acoustic oil pressure warning.

Test Conditions:

• The engine oil level is OK. Checking, refer to => [ Engine Oil ] Description and Operation.

• The engine oil temperature at least 80 °C (176 °F) (the coolant fan must start up once).

• The selector lever must be in either the "P" or "N" position.

Oil Pressure Switch, Checking:

- Remove the noise insulation.

- Remove the oil pressure switch and install it in the tester.






- Thread the oil pressure gauge into the oil filter bracket in place of the oil pressure switch.

• Pay attention to the installed position of the adapter: the cone shaped connection on the adapter is attached to the pressure hose on the tester.

- Connect the brown wire from the tester to ground (-).

- Connect the voltage tester (V.A.G 1527 B) to battery positive (B+) and the oil pressure switch (connection in the engine compartment - arrow -) using adapter cables from the connector test kit (V.A.G 1594 C). The Light Emitting Diode (LED) must not light up.






If the LED lights up:

- Replace the oil pressure switch.

If the LED does not light up:

• Watch the tester and the LED while starting the engine, since the switching point of the oil pressure switch is already being exceeded when starting.

- Start the engine and let run at idle. The LED must light up at 0.7 to 1.1 bar positive pressure, otherwise replace the oil pressure switch.

Oil Pressure, Checking:

- Check the oil pressure at different engine speeds (RPMs):

• 1500 RPM: at least 1.7 bar

• 2000 RPM: 3.0 to 5.5 bar

• above 2000 RPM: maximum 7.0 bar

If the specified values are not reached:

- Check the oil suction pipe screen for contamination.

- Check the control piston of the oil pressure relief valve for contamination.

- Check the oil pipe on the bottom of the cylinder block for leaks.

• Also, mechanical damage, for example, bearing damage can also be the cause of too low oil pressure.

• The control piston of the oil pressure relief valve is spring loaded. Therefore the highest care is required when removing/installing the plug.

• The plug in the oil pump is tightened to 35 Nm.

If no malfunction can be found:

- Replace the oil pump. Refer to => [ Oil Pump ] Oil Pump.

If the specification is exceeded:

- Check the oil passages.

- Replace the oil pump, if necessary. Refer to => [ Oil Pump ] Oil Pump.