Power Steering Pressure Switch: Testing and Inspection

Pressure Switch/Power Steering -F88-, Checking

Special tools and equipment






- VAG1526A
- VAG1594A
- VAG1598/31
- VAS5051 with VAG5051/1

or

- VAG1551 with VAG1551/3B

The pressure switch for power steering is used for idle stabilization when steering is turned to full stop (left or right).

Test sequence
- Connect VAS5051 tester or VAG1551 scan tool and select the control module for engine electronics using "address word" 01. Connecting VAS 5051/VAG1551 Scan Tool
Engine must run at idle for this.

Indicated on display:


Rapid data transfer HELP
Select function XX


- Press buttons -0- and -8- to select "Read Measuring Value Block" and press -Q- button to confirm input.

Indicated on display:


Read Measuring Value Block Q
Input display group number XXX


- Press buttons -0-, -5- and -6- to select "display group number 056" and press -Q- button to confirm input.

Indicated on display


Basic Setting 56 ->
1 2 3 4


- Check pressure switch/power steering in display field 4.

Display Group 056:

If indications do not resemble description:

Check switch
- Disconnect harness connector at pressure switch/power steering -F88-, at power steering pump.






- Connect multimeter at switch for resistance measurement.
- Start engine.
- Specification: Infinity ohms (no continuity)

- Turn steering as far to right or left as possible.
- Specification: approx. 0 ohms

If reading does not change:
- Replace pressure switch/power steering -F88-.

If indication changes:
- Check wire connections.

Checking wire connections
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Wiring and Component Testing Using VAG1598/31 Test Box






- Check the following wire connections for open circuit and short circuit to Ground (GND) and B+:

Harness connector VAG1598/31 test box
Terminal Socket
1 49
2 50

- Repair open circuit or short circuit if necessary.