Power Steering Pump: Testing and Inspection

Tool Required
^ 999 5055 Test Instrument
^ 999 5175 Coupling
^ 999 5319 Coupling
^ 998 8695 SRS Tool
^ 999 8081 Torque Wrench

NOTE: Car must be lowered when carrying out procedure.

1. Place paper over generator to protect unit from fluid.
2. Extract fluid from reservoir by suction.





3. Connect test instrument. Connect instrument between pump and steering gear pressure hose. Use couplings. Use hollow screw and washers from coupling to connect coupling.

NOTE: Connect hose between instrument cock and steering gear pressure hose. Cock should be installed with handle in line with hose.





4. Position pressure gauge in engine compartment so that it can be read from driver's seat.





5. Top up fluid level in reservoir:
a. Remove paper over generator.
b. Start engine and allow to idle. Top up fluid according as level drops. Cease topping-up when fluid stabilizes at correct level.
6. Stop engine.





7. Disconnect battery ground cable. Remove steering wheel airbag module by undoing Torx screws (two) at rear of wheel. Open connector and lift out complete module.





8. Connect tool instead of steering wheel module. Tool is used to prevent occurrence of diagnostic trouble codes (DTCs) when engine is started.
9. Reconnect battery ground cable.





10. Checking balance when turning steering wheel to right:
a. Start engine.
b. Turn wheel almost to right-hand limit. Fit torque wrench 999 8081 to steering wheel bolt. Turn wheel slowly to right with wrench and read torque when pressure gauge reading reaches 1.2 MPa (171 psi).

NOTE: It is extremely important to read the torque exactly as the gauge reading reaches 1.2 MPa (171 psi) since the pressure will remain even when the toque is reduced.





11. Checking balance when turning steering wheel to left. Turn wheel almost to left-hand limit and read torque in same manner as for right-hand side.
11. Interpreting torque readings. Torque should be between 3.2 and 4.2 Nm (2.36-3.1 ft. lbs.) and should not deviate by more than 0.7 Nm (0.5 ft. lbs.) between left and right.

NOTE: Steering gear must be replaced if deviation is greater.





12. Start engine and check pump pressure at left steering wheel limit. Turn wheel to left and hold against limit position for a maximum of 10 seconds while reading pressure gauge. Correct pressure: 7.6-8.3 MPa (5.6-6.1 ft. lbs.).
13. Check pump pressure at right steering wheel limit. Turn wheel to right and read pressure gauge as described above.





14. If pressure is incorrect, check pump capacity
a. Close cock for max. 10 seconds. If pump is fault-free, pressure gauge reading should rise to correct value of 7.6-8.3 MPa (5.6-6.1 ft. lbs.).
b. Recondition or replace pump if pressure is outside above limits.
15. Stop engine.
16. Reinstall steering wheel badge.
17. Reconnect/remove:
- Battery ground cable.
- Tool.





18. Position lower end of steering wheel module against wheel (1):
a. Reconnect connector (2).
b. Swing module into position in wheel (3) and secure with Torx screws. Tighten to 10 Nm (7.4 ft. lbs.).
c. Ensure that no wiring or components are pinched and that module is mounted securely.
19. Place protective paper over generator to protect unit from fluid.
20. Extract fluid from reservoir by suction.
21. Disconnect test instrument and couplings. Reconnect pressure hose to pump. Use new O-ring.
22. Top up fluid.





23. Turn steering wheel several times from lock to lock until fluid level has stabilized.
24. Start engine. Turn wheel from left to right end limit. Top up fluid as required.
25. Stop engine.