Oil Pressure Sender: Testing and Inspection
Oil pressure and oil pressure switch, checking
Special tools and equipment
^ VAG1342 Oil pressure gauge
^ VAG1527 B Voltage tester
^ VW 1594 A Adaptor kit
Dynamic oil pressure warning system
Function
The oil pressure switch is normally open (engine not running) and closes when minimum dynamic pressure is attained.
Oil pressure warning is activated:
approximately 10 seconds after ignition is switched ON (terminal 15 ON)
Oil pressure warning switch ON delay:
approximately 3 seconds
Oil pressure warning switch shut OFF delay:
approximately 5 seconds.
Oil pressure warning light, checking
After switching ON the ignition (engine not running), the oil pressure warning light (K3) in instrument panel must stay ON for approximately 3 seconds and then switch OFF.
Note: The check will be aborted if the engine is running.
Warning criteria
Optical oil pressure warning (oil pressure warning light flashes) and the 3 time buzzer for acoustic warning, will switch ON under the following conditions:
^ Ignition switched ON (engine NOT running) = Oil pressure switch CLOSED
^ Engine RPM greater then 1500 RPM = Oil pressure switch OPEN
^ At engine speeds greater than 5000 RPM, the oil pressure warning is not erased, even if the oil pressure switch is closed. Oil pressure warning only cancels below 5000 RPM.
^ If the oil pressure switch is opened at an engine speed greater than 1500 RPM for anywhere from 0.5 to 3 seconds, it is stored in the instrument panel Control Module. If this condition occurs 3 times during engine running, an oil pressure warning is immediately activated and since it is under 1500 RPM will not be erased. Oil pressure warning cancellation occurs when the oil pressure switch "over 1500 RPM" is closed for longer than 5 seconds or with the ignition switched OFF.
Test conditions
^ Ensure engine oil level OK
^ Oil pressure warning light K3 must light up with ignition switched ON for approximately 3 seconds
^ Engine oil temperature 80° minimum (radiator fan must have run at least once)
Note: Functional check and servicing the optical and acoustic oil pressure warning:
Refer to, Electrical Wiring Diagrams, Troubleshooting & Component Locations
Oil pressure switch, checking
Test sequence
- Remove 1.4 bar (20 psi) oil pressure switch -F1- ( black insulator), and screw into tester.
- Screw tester into oil filter flange in place of oil pressure switch.
- Connect brown wire of tester to Ground (-).
- Connect diode test lamp VAG1527 B using auxiliary cables from VAG 1594 A to battery positive (+) and oil pressure switch. LED must not light up.
If LED lights up:
- Replace 1.4 bar (20 psi) oil pressure switch -F1-, Refer to Oil Filter, Service and Repair, Oil Filter Flange Assembly, See item 11 .
If LED does not light up:
- Start engine and run at idling speed.
^ At 1.2 to 1.6 bar pressure, LED must light up
If LED does not light up:
- Replace 1.4 bar (20 psi) oil pressure switch , Refer to Oil Filter, Service and Repair, Oil Filter Flange Assembly, See (item11).
Oil pressure, checking
Test conditions
^ Oil pressure tester VAG1342 connected
^ Engine oil temperature 80° minimum
Test sequence
- Start engine and run at idling speed. Oil pressure at idle: 2.0 bar minimum
- Increase engine speed further.
- At 2000 RPM and oil temperature 80°C: Oil pressure should be between: 3.0...4.5 bar
At higher engine speeds the oil pressure must not exceed 7.0 bar (102 psi).
If specifications are not obtained:
- Correct mechanical damage, e.g. bearing damage.
- Replace oil filter flange with pressure relief valve, Refer to Oil Filter, Service and Repair, Oil Filter Flange Assembly, See (item 12 ) and / or replace oil pump, Refer to Engine Lubrication, Service and Repair, See (item 15 ).
If specification is exceeded:
- Check oil galleries.
- If necessary, replace oil filter flange with pressure relief valve.