Operation CHARM: Car repair manuals for everyone.

Line Pressure Test

Line Pressure Test

CAUTION: Carry out Line Pressure Test prior to carrying out Stall Speed Test. If line pressure is low at stall, do not carry out the Stall Speed Test or further transmission damage will occur. Do not maintain wide open throttle (WOT) in any gear range for more than 5 seconds.

NOTE: Certain sensor failures may cause high PC, failure mode effect management (FMEM) actions. Be sure that selftest and electrical repairs have been carried out or test results may be incorrect.

NOTE: The line pressure tap is used to verify output pressure from PC A or PC B by turning either one off, while verifying the output from the other solenoid. The second pressure tap is used to verify the output from the PC C solenoid.

This test verifies that the line pressure is within specification.

1. Connect the pressure gauge to the line pressure tap.
2. Start the engine and check line pressures. Refer to Line Pressure Chart to determine if line pressure is within specifications.




Line Pressure Chart - 4.0L and 4.6L Engines:





3. If the line pressure is not within specification, check the PC C pressure.
4. Connect the pressure gauge to the PC C pressure tap.





5. Start the engine and check the PC C pressure. Refer to Line Pressure Diagnosis Chart for specification.
6. If the PC C pressure is not within specification, GO to Pinpoint Test D to diagnose PC C operation. If PC C operation is OK, refer to Line Pressure Diagnosis Chart for line pressure concern causes. Test D: Pressure Control (PC) Solenoids (PCA, PCB, PCC)
7. When pressure tests are completed, install the pressure tap plugs.
^ Tighten to 13 Nm (10 lb-ft).

Line Pressure Diagnosis Chart

Line Pressure Diagnosis Chart (Part 1):




Line Pressure Diagnosis Chart (Part 2):