Component Tests and General Diagnostics

Checking power steering balance and pump pressure

Special tools:
999 5055 Pressure gauge 999 5055 Pressure Gauge
999 5175 NIPPLE 999 5175 Nipple
999 5319 CLUTCH 999 5319 Clutch
999 8081 TORQUE GAUGE 0-6 Nm 999 8081 Torque Gauge 0-6 Nm
998 8695 TEST DEVICE 998 8695 Test Device

Caution! The car must be lowered when the work is carried out.

Place paper over the generator (GEN) protection against oil






Drain oil from reservoir

Connect test instrument
Connect instrument 999 5055 Pressure gauge 999 5055 Pressure Gauge between pump and steering gear pressure hose. Use nipples 999 5175 NIPPLE 999 5175 Nipple and 999 5319 CLUTCH 999 5319 Clutch. Connect nipple 999 5175 NIPPLE 999 5175 Nipple with pipe screws and washers from the nipple 999 5319 CLUTCH 999 5319 Clutch.

Note! Connect hose from the instrument stopcock to the steering gear pressure hose. The stopcock should be in position in line with the hose.

Position the manometer in engine compartment so that it can be read off from the driver's seat






Top up fluid in reservoir




See Steering Steering.
Remove paper over the generator (GEN).

Start the engine and allow to idle. Top up with oil if the level sinks. Stop topping up when the level has stabilized at the correct level.
Shut off the engine.

Cars without SRS:
Remove steering wheel center badge

Then proceed to Checks (car without SRS).

Cars with SRS:




Remove battery negative lead
Remove the steering wheel module with the two torx screws on the reverse of steering wheel.
Separate the connector and lift out the complete steering wheel module.




Install tool 998 8695 TEST DEVICE 998 8695 Test Device instead of the steering wheel module.

The tool is used to prevent any diagnostic trouble code (DTC) being stored when the engine is started.

Install battery negative lead.

Checks

Checking balance when turning steering wheel to right




Start the engine.
Turn the steering wheel nearly all the way to the right limit position. Connect the torque wrench 999 8081 TORQUE GAUGE 0-6 Nm 999 8081 Torque Gauge 0-6 Nm to the steering wheel screw. Slowly turn to the left with the torque wrench and read off the torque when the manometer reaches 1.2 Mpa (12 kp/cm)

Caution! It is very important to read off the torque just when the manometer displays 1.2 Mpa because the pressure remains even if the torque falls.

Checking balance when turning steering wheel to left




turn the steering wheel nearly all the way to the limit position and read off the torque in the same way as for the right-hand side.

Interpreting torque readings
Torque should lie between 3.2-4.2 Nm (32-42 kpcm) and may deviate at most 0.7 Nm (7 kpcm) between right and left-hand sides.

Caution! If deviation is greater the steering gear must be exchanged.

Checking pump pressure






Start the engine and check the pump pressure at left limit position
Turn steering wheel to the left and press it to the limit position for a maximum of 10 seconds reading off the manometer at the same time.

Note! Correct pressure: 7.6-8.3 Mpa.

Check pump pressure at right limit position
Turn the steering wheel to the right limit position and read off the manometer according to the previous paragraph.

If pump pressure is faulty check pump capacity




Shut stopcock for a maximum of 10 seconds . If the pump is not faulty the manometer pressure should rise to the correct value; 7.6-8.3 Mpa .

If the pressure lies outside the above values: Recondition or replace the pump.

Shut off the engine

Reinstall steering wheel badge





Note! On cars without SRS, proceed to Final operation.

Remove:
- battery negative lead
- tool 998 8695 TEST DEVICE 998 8695 Test Device

Apply lower part of steering wheel module to the steering wheel (1)
Connect connector (2)

Fold in the steering wheel module (3) and secure with torx screws. Tighten to 10 Nm .

Check that nothing is trapped and that the steering wheel module is correctly secured.

Final operation

Position paper to protect the generator (GEN)




Drain the fluid from the reservoir

Disconnect the test instrument and the nipples. Connect the pressure pump
Use a new O-ring.

Top up the fluid
See fluid specifications see under: Steering Steering

Turn the steering wheel lock to lock until the oil level is stabilized

Start the engine. Turn steering wheel lock and lock. Top up the fluid if necessary.

Shut off the engine