Hard Steering

Hard Steering
1. Check the power assist.
Is the initial turning load more than 29 N (3.0 kgf, 6.6 lbs)?
YES - Go to step 2.
NO - Power assist is OK.

2. Connect the P/S pressure gauge T/N 074060010001 or T/N 07406-001000A to the pump.
3. Measure steady-state fluid pressure from the pump at idle with T/N 07406-0010001 or T/N 07406-001000A.
Is the pressure 1,470 kPa (15 kgf/cm2, 213 psi) or less?
YES - Go to step 4.
NO - Go to step 8.

4. Measure the pump relief pressure at idle with T/N 07406-0010001 or T/N 07406-001000A.
Is the pressure 9,604 - 9,996 kPa (98 - 102 kgf/cm2, 1,392 - 1,448 psi) or more?
YES - Go to step 5.
NO - Go to step 9.

5. With a spring scale, measure the power assist in both directions, to the left and to the right.
Are the two measurements within 5.0 N (0.51 kgf, 1.12 lbs) of each other?
YES - Go to step 6.
NO - Go to step 11.

6. Measure the fluid pressure with T/N 07406-0010001 or with T/N 07406-001000A with both pressure gauge valves open (if so equipped), while turning the steering wheel fully to the left and fully to the right.
Is the pressure 9,604 - 9,996 kPa (98 - 102 kgf/cm2, 1,392 - 1,448 psi) or more?
YES - Go to step 7.
NO - Faulty gearbox.

7. Adjust the rack guide and retest.
Is the steering OK?
YES - Repair is completed.
NO - Faulty gearbox.

8. Check for feed and return lines between the pump and the gearbox for clogging and deformation.
Are the lines clogged or deformed?
YES - Repair or replace the lines.
NO - Faulty valve body unit.

9. Disassemble the pump.
10. Check the flow control valve for smooth movement and leaks.
Is the flow control valve OK?
YES - Faulty pump assembly.
NO - Faulty flow control valve.

11. Check the cylinder lines A and B for deformation.
Are the A or B lines deformed?
YES - Replace the lines.
NO - Go to step 12.

12. Check for a bent rack shaft or misadjusted rack guide (too tight).
Is the rack shaft bent or the rack guide adjusted too tight?
YES - Replace the rack shaft or readjust the rack guide.
NO - Faulty valve body unit.