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Line Pressure Test

  1. Perform the mechanical system test preparation. (See MECHANICAL SYSTEM TEST PREPARATION .)
  2. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  3. Remove the following parts as a single unit. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [(VIN 7 & VIN L) (US)] .)
    • Air cleaner cover
    • Air cleaner element
    • Fresh-air duct
    • Air cleaner case
    • Air hose
    • Resonance chamber
  4. Remove the bolts and set the wiring harness and wiring harness bracket in a place which does not interfere with servicing.
    G13176902Courtesy of MAZDA MOTORS CORP.
  5. Remove the pressure detection square head plug.
    WARNING:
    • Do not remove the square head plug when the ATF temperature is high. Otherwise, ATF could overflow and cause severe burns or serious injury. Remove the square head plug when the transaxle and ATF temperatures are low.
    NOTE:
    • Use a suitable oil pressure gauge that corresponds to the line pressure because the maximum scale value differs depending on the oil pressure gauge.
    Fig 1: Oil Pan, Dipstick, Square Head Plug With Torque Specification
    G12231638Courtesy of MAZDA MOTORS CORP.
  6. Install SSTs (49 D019 908, 49 D019 909, 49 D019 910, 49 D019 911, 49 D019 913) to the line pressure detection port as shown in the figure.
    G11429162Courtesy of MAZDA MOTORS CORP.
  7. Install the following parts as a single unit. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [(VIN 7 & VIN L) (US)] .)
    • Air cleaner cover
    • Air cleaner element
    • Fresh-air duct
    • Air cleaner case
    • Air hose
    • Resonance chamber
  8. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  9. Start the engine.
  10. Warm up the engine until the ATF temperature is 60-70°C {140-158°F}.
  11. Shift the selector lever to the D position.
  12. Measure the line pressure while idling in D position.
  13. Measure the line pressures while idling in the M (1st gear) and R positions using the same procedure.
  14. Stop the engine.
  15. Change the low-pressure gauge (49 D019 908) to the high-pressure gauge (49 D019 907).
    G11429163Courtesy of MAZDA MOTORS CORP.
  16. Start the engine.
  17. Measure the line pressure while stalling in D position.
    1. Strongly depress the brake pedal with the left foot.
    2. Shift the selector lever to the D position.
      CAUTION:
      • To prevent damage to the transaxle, measure the line pressure while stalling (Step (3)-(4)) within 5s.
    3. Slowly depress the accelerator pedal fully with the right foot all the way down.
    4. Read the line pressure quickly while stalling, and remove the right foot from the accelerator pedal.
    5. Shift the selector lever to the N position and idle for 1 min or more.
  18. Measure the line pressure while stalling for positions other than D in the same procedure.
    • If there is any malfunction, one of the following causes may have occurred.
      Condition Possible cause
      Lower than specification Lower in R, D, and M (1GR) position
      • Oil pump wear
      • ATF leakage from oil pump, control valve body, and transaxle case
      • Pressure regulator valve sticking
      • Pressure control solenoid operation malfunction
      • Solenoid reducing valve sticking
      Lower in D and M (1GR) position
      • ATF leakage from low clutch hydraulic circuit
      Lower in R and M (1GR) position
      • ATF leakage from low and reverse brake hydraulic circuit
      Lower in R position
      • ATF leakage from R-3-5 brake hydraulic circuit
      Higher than specification Higher in R, D, and M (1GR) position
      • Pressure regulator valve sticking
      • Pressure control solenoid operation malfunction

      Line pressure 

      Measurement conditions Specification (kPa {kgf/cm2 , psi})
      Idling R position 500-700 {5.10-7.13, 72.6-101.0}
      D and M (1GR) position 330-470 {3.37-4.79, 47.9-68.1}
      Stalling R position 1, 790-2, 100 {18.26-21.41, 259.7-304.5}
      D and M (1GR) position 970-1, 170 {9.90-11.93, 141.0-169.6}
  19. Stop the engine.
  20. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  21. Remove the following parts as a single unit. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [(VIN 7 & VIN L) (US)] .)
    • Air cleaner cover
    • Air cleaner element
    • Fresh-air duct
    • Air cleaner case
    • Air hose
    • Resonance chamber
  22. Remove the SSTs.
    WARNING:
    • If the SST is removed when the ATF temperature is high, ATF could overflow and cause severe burns or serious injury. Remove the SST when the transaxle and ATF temperatures are low.
  23. Install a new square head plug.
    Fig 2: Oil Pan, Dipstick, Square Head Plug With Torque Specification
    G12231638Courtesy of MAZDA MOTORS CORP.
    NOTE:
    • Do not reuse the square head plug because a sealant coating has been applied.
  24. Tighten the wiring harness bracket installation bolts in the order shown in the figure.
    Fig 3: Wiring Harness Bracket Bolts With Torque Specification
    G13715734Courtesy of MAZDA MOTORS CORP.
  25. Install the following parts as a single unit. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [(VIN 7 & VIN L) (US)] .)
    • Air cleaner cover
    • Air cleaner element
    • Fresh-air duct
    • Air cleaner case
    • Air hose
    • Resonance chamber
  26. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
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