Power Steering Pressure Switch Check

Required Special Tools: 

• MB990662: Power Steering Oil Pressure Gauge
• MB991548: Power Steering Oil Pressure Gauge Adapter (Pump Side)
• MB991549: Power Steering Oil Pressure Gauge Adapter (Hose Side)

1. Disconnect the pressure hose from the oil pump, and then connect the special tools MB991548, MB990662 and MB991549.
2. Bleed air, and then turn the steering wheel several times while the vehicle is not moving so that the temperature of the fluid rises to approximately 50 - 60° C (122 - 140° F).
3. The engine should be idling.
4. Disconnect the connector for the oil pressure switch, and place an ohmmeter at the switch.
5. Gradually close the shut-off valve of the pressure gauge and increase the hydraulic pressure, then check whether or not the hydraulic pressure that activates the switch is the standard value.

   Standard value: 1.8 - 2.4 MPa (261 - 348 psi) 

6. Gradually open the shut-off valve and reduce the hydraulic pressure; then check whether or not the hydraulic pressure that deactivates the switch is the standard value.

   Standard value: 1.0 - 2.4 MPa (145 - 348 psi) 

7. Remove the special tools MB991548, MB990662 and MB991549, and then tighten the pressure tube flare nut to the specified torque.

   Tightening torque: 18 +/- 3 N. m (13 +/- 2 ft-lb) 

8. Bleed the system (Refer to POWER STEERING SYSTEM AIR BLEEDING  ).
   Fig 1: Checking Power Steering Pressure Switch

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.