Measurement Of Steering Effort

Does the steering warning light illuminate?

Yes:  Using Subaru Select Monitor, read the DTC and inspect according to it. Ref. to OPERATION .

No  : Go to  2.

1. Using Subaru Select Monitor, display the data of [EPS operating condition]. Ref. to OPERATION .
2. Connect the Subaru Select Monitor, and turn the steering wheel. (One lock to lock)

Is the [EPS operating condition] normal without displaying any DTC code?

Yes:  Go to  3.

No  : If the [EPS operating condition] is "Assist limitation", stop the engine for approx. 30 minutes and perform the procedures from step  1 again.

1. Stop the vehicle on paved road.
2. Set the tire air pressure to the specification.
3. Start the engine.
4. Run the engine at idle.
5. Install a spring scale on the steering wheel tangent.
6. Pull the spring scale at a right angle to the steering wheel, and measure both right and left steering wheel efforts.

Courtesy of SUBARU OF AMERICA, INC.

Is the steering effort less than 31 N (3.2 kgf, 7.0 lbf)?

Yes:  Go to  4.

No  : Go to  8.

1. Stop the engine.
2. Pull the spring scale at a right angle to the steering wheel, and measure both right and left steering wheel efforts.

Is the steering effort less than 294.2 N (30.0 kgf, 66.2 lbf)?

Yes:  Go to  5.

No  : Perform the inspection or adjustment around the suspension part.

1. Display the data of [Torque sensor main output] and [Torque sensor sub output] using Subaru Select Monitor. Ref. to DATA MONITOR .
2. Read the value of torque sensor.

Is the torque value ±0.75 N.m (0.08 kgf-m, 0.05 ft-lb)?

Yes:  Go to  6.

No  : Replace the gearbox assembly. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>ELECTRIC POWER STEERING GEARBOX .

1. Remove the universal joint LWR.
2. Display the data of [Torque sensor main output] and [Torque sensor sub output] using Subaru Select Monitor. Ref. to DATA MONITOR .
3. Read the value of torque sensor.

Is the torque value ±0.75 N.m (0.08 kgf-m, 0.05 ft-lb)?

Yes:  Go to  7.

No  : Replace the gearbox assembly. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>ELECTRIC POWER STEERING GEARBOX .

1. Remove the universal joint LWR.
   NOTE: Check that the universal joint assembly - steering moves up and down smoothly without installing the bolt. Then tighten the bolts first on the gearbox side and then on the column shaft side.
2. Display the data of [Torque sensor main output] and [Torque sensor sub output] using Subaru Select Monitor.
3. Read the value of torque sensor.

Is the torque value ±0.75 N.m (0.08 kgf-m, 0.05 ft-lb)?

Yes:  Go to  8.

No  : Check the universal joint assembly steering. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>UNIVERSAL JOINT>INSPECTION .

1. Remove the universal joint LWR.
2. Measure the steering wheel effort.

Is the steering effort less than 2.26 N (0.23 kgf, 0.51 lbf)?

Yes:  Go to  9.

No  : Replace the column assembly steering. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>STEERING COLUMN .

Measure the steering wheel effort.

Is the difference of steering effort between right and left less than 20%?

Yes:  Go to  10.

No  : Replace the column assembly steering. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>STEERING COLUMN .

Measure the swing torque of joint. (Yoke of column assembly - steering side) Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>UNIVERSAL JOINT>INSPECTION .

Is the swing torque of the universal joint UPR less than 5.4 N (0.55 kgf, 1.21 lbf)?

Yes:  Go to  11.

No  : Replace the universal joint UPR with a new part. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>UNIVERSAL JOINT .

Measure the swing torque of joint. (Yoke of gearbox side) Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>UNIVERSAL JOINT>INSPECTION .

Is the swing torque of the universal joint LWR less than 4.5 N (0.46 kgf, 1.01 lbf)?

Yes:  Go to  12.

No  : Replace the universal joint LWR with a new part. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>UNIVERSAL JOINT .

Check the front wheels.

Does the front wheels have unsteady revolution or rattling, or does the brake drag?

Yes:  Inspect, readjust and replace if necessary.

No  : Go to  13.

Remove the tie-rod ends.

Does the tie-rod ends of suspension have unsteady revolution or rattling?

Yes:  Inspect and replace if necessary.

No  : Go to  14.

Remove the ball joint.

Does the ball joints of suspension have unsteady revolution or rattling?

Yes:  Inspect and replace if necessary.

No  : Go to  15.

Measure the rotating of gearbox.

Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>ELECTRIC POWER STEERING GEARBOX>INSPECTION>LIMIT .

Is the rotational resistance of the steering gearbox less than 20 N (2.0 kgf, 4.5 lbf)? Is the difference between the right and left rotational resistances less than 20%?

Yes:  Go to  16.

No  : Replace the gearbox assembly. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>ELECTRIC POWER STEERING GEARBOX .

Measure the sliding of gearbox.

Is the sliding resistance of the steering gearbox less than 397 N (40.5 kgf, 89.3 lbf)? Is the difference between the right and left sliding resistances less than 20%?

Yes:  Steering effort is normal.

No  : Replace the gearbox assembly. Ref. to POWER ASSISTED SYSTEM (POWER STEERING)>ELECTRIC POWER STEERING GEARBOX .