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Secondary Pressure Test: Inspection

CAUTION:
  • Vehicle components are extremely hot immediately after driving and performing the secondary pressure test. Be wary of receiving burns from heated parts.
  • Make sure no other person is around the vehicle during secondary pressure test measurement.
  • After performing the secondary pressure test measurement, adjust the CVTF level.
NOTE:
  • If the pulley and variator chain, clutch or brake show signs of slipping or shift feel is not correct, check the secondary pressure.
  • Connect Subaru Select Monitor to vehicle so as to measure the engine speed and actual secondary pressure.
  • In many cases, slippage or driving inability may be due to insufficient oil pressure for the operation of clutch, brake or control valve.
  1. Lift up the vehicle.
  2. Remove the front wheel RH. Ref. to WHEEL AND TIRE SYSTEM>TIRE AND WHEEL>REMOVAL .
  3. Remove the plug.
    G09481925Courtesy of SUBARU OF AMERICA, INC.
  4. Attach ST1, ST2 and ST3 to transmission.

    Preparation tool: 

    ST1: OIL PRESSURE GAUGE ASSY (18801AA000)

    ST2: PRESSURE GAUGE ADAPTER (18681AA000)

    ST3: OIL PRESSURE ADAPTER SET (498897700)

    NOTE: Use the ST2 with genuine O-ring (part No. 806911080) attached.
    G13199972Courtesy of SUBARU OF AMERICA, INC.
  5. Install the front wheel RH. Ref. to WHEEL AND TIRE SYSTEM>TIRE AND WHEEL>INSTALLATION .
  6. Lower the vehicle.
  7. Set the gauge so that it can be seen from the driver's seat.
  8. Using the Subaru Select Monitor, check if the throttle valve operates when you depress the accelerator pedal. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DATA MONITOR>LIST .
  9. Check the engine oil level. Ref. to LUBRICATION (H4DOTC)>ENGINE OIL>INSPECTION .
  10. Check the engine coolant level. Ref. to COOLING (H4DOTC)>ENGINE COOLANT>INSPECTION .
  11. Adjust the CVTF level. Ref. to CONTINUOUSLY VARIABLE TRANSMISSION (TR690)>CVTF>ADJUSTMENT .
  12. Increase the CVTF temperature to 60 - 80°C (140 - 176°F) by idling the engine with the select lever shifted to "N" or "P" range.
  13. Hold down the pre-collision brake OFF switch to turn OFF the pre-collision brake.
  14. Shift the select lever to "D" range.
  15. Depress the accelerator pedal to the full while fully depressing the brake pedal with your left foot.
  16. Immediately after the engine speed becomes steady, record the reading of the secondary pressure, engine speed and actual secondary pressure on Subaru Select Monitor. And then release the accelerator pedal. Shift the select lever to "N" range, and cool down the engine by idling it for one minute or more.
    NOTE:
    • Do not continue the secondary pressure test for 5 seconds or more at a time (from fully closed throttle, fully open throttle to secondary pressure reading). Failure to follow this instruction will cause the engine oil and CVTF to deteriorate and the clutch and brake to be adversely affected.
    • After performing the secondary pressure test, be sure to cool down the engine for at least one minute with the select lever set in "P" or "N" range and with the idle speed at 1, 200 r/min or less.
    • Under each condition, check that the measured pressure matches almost totally with actual secondary pressure.
    • When both measured pressure and actual secondary pressure are out of specification, judge as control valve malfunction.
    • The value at stall is for reference because the pressure changes under different conditions or circumstances.
    • The value at idling is steady because it is not affected by any condition or circumstance.
    Secondary pressure standard
      Range Throttle Brake Secondary pressure (MPa (kgf/cm2 , psi))
    Stall D, R Full open ON 4.5 - 6 (45.9 - 61.2, 652 - 870)
    Idling P, N Full closed OFF 0.3 - 1.5 (3.1 - 15.3, 44 - 218)
  17. Remove the ST.
  18. Install the plugs with new O-rings.
    CAUTION:
    • Before installing O-rings, apply sufficient amount of CVTF to avoid damage and deformation.
    • Use SUBARU genuine CVTF.
    • Be careful not to incorrectly install or fail to install O-rings and other such parts.

    Tightening torque: 

    25 N.m (2.5 kgf-m, 18.4 ft-lb)