Checking delivery pressure of motor/pump unit

Special tools and workshop equipment required

• Power steering tester - V.A.G 1402-
• Adapter - V.A.G 1402/20-
• Adapter - V.A.G 1402/21-
• Hose from adapter set - V.A.G 1402/6-

Vehicles with air filter on left in engine compartment

• Remove battery and battery tray ⇒ Electrical system; Rep. gr. 27; Battery; Removing and installing battery.

Continued for all vehicles

• Unscrew cap -1- from motor/pump unit -2-.
• Draw off as much hydraulic fluid as possible from motor/pump unit using a suction bottle.
• Remove noise insulation for engine ⇒ General body repairs, exterior; Rep. gr. 50; Assembly overview - noise insulation.
• Remove pressure pipe on motor/pump unit.

• Assemble adapter as shown in figure.

• 1 Motor/pump unit
• 2 Power steering tester - V.A.G 1402-
• 3 Hose from adapter set - V.A.G 1402/6-
• 4 Adapter - V.A.G 1402/21-
• 5 Pressure line
• 6 Adapter - V.A.G 1402/20-

Ensure that lever on pressure gauge is in position -2-.

• Fill up with hydraulic fluid and check fluid level ⇒ 7.3 Checking hydraulic fluid level of power steering.
• Bleed steering system ⇒ 7 Bleeding steering system, checking for leaks and checking fluid level.
• Now check delivery pressure.

Prerequisites for testing:

• System must be free of leaks
• Hoses and lines must not be kinked or restricted

• Start engine.

Drawing as above ⇑

• With engine idling, close shut-off valve (position -1-) for no longer than 5 seconds and note pressure.

Specification for delivery pressure:

90 to 105 bar

If specification is not attained, renew motor/pump unit ⇒ 6.2 Removing and installing motor/pump unit.

Turn steering wheel to full lock and hold in that position (shut-off valve in position -2-) - read off pressure.

If the reading is significantly lower than the first measured value then there is a leak in or on the steering rack.

• Remove pressure gauge and adapter.
• Attach pressure line to motor/pump unit.
• Fill up with hydraulic fluid and check fluid level ⇒ 7.3 Checking hydraulic fluid level of power steering.
• Bleed steering system ⇒ 7 Bleeding steering system, checking for leaks and checking fluid level.
• Check hydraulic fluid level and top up if necessary ⇒ 7.3 Checking hydraulic fluid level of power steering.
• Check steering system for leaks ⇒ 7.2 Check steering system for leaks.
• Install noise insulation.

Specified torques