Oil Temperature Sensor/Switch: Testing and Inspection

Oil Pressure and Oil Pressure Switch, Checking

--> [ Oil Pressure Switch, Checking ]

--> [ Oil Pressure, Checking ]

Special tools, testers and auxiliary items required

• Oil pressure gauge (VAG 1342)

• Adapter (VAG 1342/14)

• Voltage tester (VAG 1527 B)

• Connector test set (VAG 1594C)

• Wiring diagram

• Function test and servicing the optical and acoustic oil pressure indicator.

Test Conditions

• Engine oil level OK.

• Engine oil temperature at least 80 °C (radiator fan must start up once)

• Selector lever must be in the "P" or "N" position.

Oil Pressure Switch, Checking

Oil pressure, checking. Refer to --> [ Oil Pressure, Checking ].

Procedure

- Remove oil pressure switch (F1) --> [ (Item 6) , 20 Nm ] Service and Repair, and install into oil pressure gauge.





- Install oil pressure gauge (VAG 1342) with adapter (VAG 1342/14) into oil filter bracket in place of oil pressure switch.

• Observe installation position of adapter (VAG 1342/14): The conical connection of the adapter is threaded in with the pressure hose of the oil pressure gauge (VAG 1342).

- Connect brown wire of oil pressure gauge (VAG 1342) to ground (-).

- Connect voltage tester (VAG 1527B) using adapter cables from connector test set (VAG 1594C) to battery B+ and oil pressure switch (F1). LED must not light up.

If the LED lights up:

- Replace the oil pressure switch (F1) --> [ (Item 6) , 20 Nm ] Service and Repair.

If the LED does not light up:

• While starting engine, watch pressure tester and Light Emitting Diode (LED) as switch point of oil pressure switch may already be exceeded during start.

- Start the engine and run at idle speed.

LED must light up at 1.2 to 1.6 bar positive pressure, otherwise replace oil pressure switch (F1) --> [ (Item 6) , 20 Nm ] Service and Repair.

Oil Pressure, Checking

- Check oil pressure at different speeds:

• 1500 RPM: at least 1.7 bar

• 2000 RPM: 3.0 to 5.5 bar pressure

• Above 2000 RPM: maximum 7.0 bar

- If the specified values are not reached:

- First check control piston of oil pressure relief valve in oil pump for contamination.

- To do so, first remove sealing plug from cylinder block, then remove sealing plug from oil pump.

• Control piston of oil pressure relief valve is spring loaded. Therefore the highest care is required when removing the sealing plug.

• The locking bolt is tightened in oil pump to 35 Nm.

- Pull control piston out of oil pump and remove contamination if necessary.

- Then check strainer in oil intake connection --> [ (Item 17) Oil intake connection ] Oil Pan, Pump and Filter Bracket Assembly Overview for contamination.

- Also check oil pipe on cylinder block at bottom --> [ (Item 10) Oil pipe ] Oil Pan, Pump and Filter Bracket Assembly Overview for leaks. Replace sealing rings --> [ (Item 9) Seal ] Oil Pan, Pump and Filter Bracket Assembly Overview if necessary.

- Correct mechanical damage, e.g. bearing damage.

At higher engine speeds oil pressure must not exceed 7.0 bar

If a malfunction is found despite insufficient oil pressure:

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

If the specification is exceeded:

- Check oil channels.

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