Oil Pressure Switch (For Fuel Pump): Testing and Inspection

Oil Pressure and Pressure Switch, Checking

Special tools, testers and auxiliary items required
^ Oil Pressure Gauge VAG 1342
^ Voltage Tester VAG 1527B
^ Connector Test Set VAG 1594C

Requirements
^ Engine oil level OK.
^ Engine oil temperature at least 80 degree C (radiator fan must start up once).

Note:
^ Function test and servicing the optical and acoustic oil pressure indicator. wiring diagrams, "Function and Component Selection".

Test Sequence





- Remove oil pressure switch F1 and screw into oil pressure gauge.
- Thread oil pressure gauge into oil filter bracket in place of oil pressure switch.
- Connect brown wire of tester to ground.
- Connect voltage tester V.A.G 1527B using adapter cables from connector test kit V.A.G 1594C to B+ and oil pressure switch. LED must not light up.
- If LED lights up, replace 1.4 bar oil pressure switch F1

If LED does not light up:

- Start engine and increase engine speed: LED must light up at 1.2 to 1.6 bar positive pressure, otherwise replace oil pressure switch.
- Increase engine speed further. At 2000 rpm and an oil temperature of 80 degree C, the oil pressure should be between 2.7 to 4.5 bar.

At higher engine speeds oil pressure must not exceed 7.0 bar

If specification is not obtained:

- Check screen in oil intake pipe for contamination.

Note:
^ Also, mechanical damage e.g. bearing damage can also be the cause of too low oil pressure.

If no malfunction can be found:

- Replace oil pump.

If specification is exceeded:

- Check oil channels.