Power Assist Check
With Vehicle Parked1. Check the power steering fluid level and pump belt tension.
2. Start the engine, let it idle, and turn the steering wheel from lock-to-lock several times to warm up the fluid.
3. Attach a commercially available spring scale to the steering wheel. With the engine idling and the vehicle on a clean, dry floor, pull the scale as shown and read it as soon as the tires begin to turn.
- If the scale reads no more than 25 N (2.5 kgf, 5.5 lbs.) the gearbox and pump are OK.
- If the scale reads more than 25 N (2.5 kgf, 5.5 lbs.), go on step 4.
4. Stop the engine. Disconnect the sensor inlet hose (A) from the power steering speed sensor (B), and plug (C) the hose and sensor fitting. (The VSS connector is only on vehicles equipped with the navigation system).
5. Start the engine, and let it idle.
- If the scale reads still more than 25 N (2.5 kgf, 5.5 lbs.) the power steering speed sensor is OK.
The problem maybe the pump or gearbox.
- Measure the pump pressure with T/N 07406-0010001 or with T/N 07406-001000A.
- Check the rack guide adjustment.
- If the scale reads 25 N (2.5 kgf, 5.5 lbs.) or less, check for fluid leaks at the speed sensor inlet hose. If there are no leaks in the hose, the power steering speed sensor is leaking internally. Replace the speed sensor.
Road Speed
Special Tools Required
Bypass tube joint 07406-0010101 (Included with 07406-0010001 or 07406-001000A)
1. Check the power steering fluid level and pump belt tension.
2. Start the engine, let it idle, and turn the steering wheel from lock-to-lock several times to warm up the fluid.
3. Stop the engine, to simulate speeds above 62 mph (100 km/h), disconnect the sensor inlet hose (A) and sensor outlet hose (B) from the power steering speed sensor (C), and connect them to the bypass tube joint (D). Plug (E) the end of the bypass tube joint (The vehicle speed pulse connector is only on vehicles equipped with the navigation system).
4. Attach a commercially available spring scale to the steering wheel. Start the engine, with the idling and vehicle on a clean, dry floor, pull the scale as shown and read it as soon as the tires begin to turn.
- If the scale reads more than 25 N (2.5 kgf, 5.5 lbs.) the valve body unit is OK. The problem is in the power steering speed sensor, replace it and road test.
- If the scale reads 25 N (2.5 kgf, 5.5 lbs.) or less, problem is in the pump. Check the pump pressure with T/N 07406-0010001, or with T/N 07406-001000A.