
3. HYDRAULI C/ MECHANI CAL DIAGNOSIS
The information regarding the hydraulic/mechanical diagnosis of the automatic transmission as fitted to V2 Series
Models carries over from the information provided for VX Series Models, noting the following:
• A revised pressure control solenoid was introduced with the MY2003 automatic transmissions, resulting in a
new pressure checking procedure and results.
For information relating to the hydraulic/mechanical diagnosis of the Hydra-Matic 4L60-E automatic transmission
fitted to V2 Ser ies Models not c over ed in this Sec tion, r ef er to Sectio n 7C3 – HY DRA-MATIC 4L60-E AUTOM ATIC
TRANSMISSION – HYDRAULIC/MECHANICAL DIAGNOSIS, in the VX Series Service Information.
3.1 LINE P RE SSURE CHECK
PRELIMINARY INFORMATION
Line pressures are calibrated for two sets of gear ranges – Drive/Park/Neutral and Reverse. This allows the
transmission line pressure to be appropriate for two different pressure needs in different gear ranges:
Gear Range Line Pressure Range
Drive, Park or Neutral...... 380 – 1,300 kPa
Reverse........................... 440 – 2,235 kPa
Before performing a line pressure check, verify that the pressure control (PC) solenoid is receiving the correct
electrical signal from the PCM, as follows:
1. Install Tech 2. Refer to 3.1 CONNECTING TECH 2 TO THE VEHICLE in Section 0C - TECH 2, in the VX
Series I Service Information for the necessary procedure.
2. Start the engine and firmly apply the park brake.
3. Check for stored diagnostic trouble code/s (DTC) and in particular, for a pressure control solenoid DTC.
4. Rectify as necessary.
NOTE: The transmission may experience harsh, soft or mushy shifts for up to two days after this procedure.
PROCEDURE
1. Check engine and transmission fluid levels.
2. Check the manual linkage for correct adjustment and wear.
3. If not previously carried out, install Tech 2 to the vehicle. Refer to 3.1 CONNECTING TECH 2 TO THE
VEHICLE in Section 0C - TECH 2, in the VX Series I Service Information for the necessary procedure.
4. Install an oil pressure gauge such as Tool
J21867 or commercial equivalent, into the line
pressure tapping point on the transmission, as
shown.
5. Select ‘P’ (Park) range and firmly apply the
park brake.
6. Start the engine and allow to warm up, at idle.
7. Access ‘Miscellaneous Tests’ on Tech 2, then
the PCS CONTROL test.
8. Increase ACTUAL PCS in 0.1 Amp increments
on Tech 2 and read the corresponding line
pressure reading on the fluid pressure gauge.
(Allow the pressure to stabilise for 5 seconds
after each current change.
9. Compare the pressure readings against the line
pressures provided in the following chart.
IMPORTANT: Total test running time should not
exceed 2 minutes or transmission damage could
occur.
Figure 7C-5
NOTE 1: Pressures are to be taken at an engine speed of 1,500 rpm and a temperature of 66°C. Line pressure
drops as temperature increases.
NOTE 2: If pressure readings differ greatly from the line pressure chart, refer to the Diagnostic Section in either
Section 6C1 POWERTRAIN MANAGEMENT – V6 SUPERCHARGED ENGINE or Section 6C3 POWERTRAIN
MANAGEMENT – GEN III V8 ENGINE in the VX Series Service Information.
NOTE 3: T ech 2 is only able to control the PC solenoid in Park , and Neutral, with the vehicle stopped. This protects
the clutch packs from extremely high or low pressures in Drive or Reverse ranges.