Oil Pressure Sender: Testing and Inspection

Oil Pressure and Oil Pressure Switch, Checking

Special tools






^ V.A.G 1342 Oil pressure tester
^ V.A.G 1527 B Voltage tester
^ VW 1594 A Adaptor kit

Dynamic of 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: approx. 10 seconds after ignition is switched ON (terminal 15 ON)
Oil pressure warning switch ON delay: approx. 3 seconds
Oil pressure warning switch shut OFF delay: approx. 5 seconds

Oil pressure warning light, checking

After switching ON the ignition (engine not running), the oil pressure warning light (K3) must stay ON for approx. 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 than 1500 rpm = Oil pressure switch OPEN
^ At engine speeds greater than 5000 rpm, the oil pressure warning is not cancelled, 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 Page 1 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 approx. 3 seconds
^ Engine oil temperature 80°C minimum

Oil pressure switch, checking






- 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 pressure switch.
- Connect brown tester wire to engine Ground.
- Connect V.A.G 1527 B Voltage tester between battery Positive and oil pressure switch using jumper wires from VW 1594 adaptor kit.
^ LED must not illuminate

If LED is illuminated:

- Replace 1.4 bar (20 psi) oil pressure switch -F1-.

If LED is not illuminated:

- Start engine and let idle.
^ At 1.2 to 1.6 bar, LED must light up

If LED does not light up
- Replace 1.4 bar (20 psi) oil pressure switch -F1-.

Oil pressure, checking

Test conditions

^ Oil pressure tester V.A.G 1342 connected
^ Engine oil temperature 80°C minimum

Test procedure

- Oil pressure at idle: 2.0 bar minimum
- Oil pressure at 2000 rpm: 3.0 to 4.5 bar

If specifications not obtained:

- Replace oil filter assembly (W/ pressure relief valve) and/or replace oil pump.
Oil pressure should not exceed 7.0 bar (102 psi).
- Replace oil filter flange with pressure check valve.