Symptom Troubleshooting

1. Check the power assist (see POWER ASSIST CHECK  ).

   Is the power assist more than 29 N (3.0 kgf, 6.6 lbf)? 

   1. YES  - Go to step 2.
   2. NO  - Power assist is OK.
2. Measure steady-state fluid pressure from the pump at idle with T/N 07406-0010001 (see step 10 on Pump Pressure Test with T/N 07406-0010001  ) or with T/N 07406-001000A (see step 9 on Pump Pressure Test with T/N 07406-001000A  ).

   Is the pressure 1,500 kPa (15 kgf/cm ²  , 213 psi) or less? 

   1. YES  - Go to step 3.
   2. NO  - Go to step  7 .
3. Measure the pump relief pressure at idle with T/N 07406-0010001 (see step 10 on PUMP PRESSURE TEST WITH T/N 07406-0010001  ) or T/N 07406-001000A (see step 9 on PUMP PRESSURE TEST WITH T/N 07406-001000A  ).

   Is the pressure 8,300-8,800 kPa (85-90 kgf/cm ²  , 1,210-1,280 psi) or less? 

   1. YES  - Go to step 4.
   2. NO  - Go to step  8 .
4. 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 lbf) of each other? 

   1. YES  - Go to step 5.
   2. NO  - Go to step  9 .
5. Measure the fluid pressure with T/N 07406-0010001 (see step 12 on PUMP PRESSURE TEST WITH T/N 07406-0010001  ) or with T/N 07406-001000A (see step 11 on PUMP PRESSURE TEST 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 8,300-8,800 kPa (85-90 kgf/cm ²  , 1,210-8 1,280 psi) or less? 

   1. YES  - Go to step 6.
   2. NO  - Faulty gearbox.
6. Adjust the rack guide (see RACK GUIDE ADJUSTMENT  ), and retest.

   Is the steering OK? 

   1. YES  - Repair is completed.
   2. NO  - Faulty gearbox.
7. Check for feed and return lines between the pump and the gearbox for clogging and deformation.

   Are the lines clogged or deformed? 

   1. YES  - Repair or replace the lines.
   2. NO  - Faulty valve body unit.
8. Check the flow control valve (see step 9 on PUMP OVERHAUL  ) for smooth movement and leaks.

   Is the flow control valve OK? 

   1. YES  - Faulty pump assembly.
   2. NO  - Faulty flow control valve.
9. Check the cylinder lines A and B for deformation (see STEERING GEARBOX OVERHAUL  ).

   Are the A or B lines deformed? 

   1. YES  - Replace the lines.
   2. NO  - Go to step 10.
10. Check for a bent rack shaft or misadjusted rack guide (too tight).

Is the rack shaft bent or the rack guide adjusted too tight? 

1. YES  - Replace the rack shaft or readjust the rack guide.
2. NO  - Faulty valve body unit.