Measuring the Pressure

Measuring the hydraulic pressure

Note: Hydraulic fluid must not be allowed to come into contact with upholstery or paintwork.




1. The top must be up.
2. Release the handbrake (to put slack in the cable over the servo pump).
3. Remove the rear-seat cushion.
4. Check the level of hydraulic fluid in the system and top up as necessary.
5. Check to see whether there is an excessive amount of air in the system. If so, the system must be bled before the pressure can be measured.




6. Disconnect the hoses from the tee pieces to the rear of the pump. Plug the open ends using the hose union contained in hose kit 8292815.
Place absorbent paper underneath the pump to soak up any spilt fluid.




7. Remove the tee piece and connect adaptor 87 91 584 in its place.




8. Connect pressure sensor 89 95 522 to the hose contained in hose kit 82 92 815.




9. Connect the other end of the hose to the adaptor on the pump.




10. Connect the ABS-system tester to the battery.
11. Connect the pressure sensor to the ABS tester.
12. Set the ABS tester to measure pressure.
13. Measure the pressure as follows:
- Start the car and press the switch to lower the top.
- Hold down the switch until the overload protector breaks the circuit. Now read oft the pressure from the ABS tester.
Minimum working pressure: 25 bar (365 psi).

Note: The presence of air inside the adaptor fitting can give rise to spurious pressure readings. Run the pump briefly in the opposite direction to expel any air bubble. Read the pressure again.

14. Disconnect the ABS tester.
15. Disconnect the pressure sensor from the hose and adaptor.




16. Remove the adaptor from the pump, tilting the pump to avoid fluid spillage.




17. Screw on the tee piece.




18. Disconnect the hose union and reconnect the hoses to the pump. Make sure the hoses run underneath the handbrake cable. Press the pump home in its mounting. Tightening torque: 5.1 - 6.2 Nm (3.8 - 4.5 ft lb).
19. Put back the seat cushion.