Checking hydraulic pressure
|
|
Checking hydraulic pressure
|
The hydraulic pressure can be tested by measuring the system pressure in the D and R positions in the idling and stalling modes. The test will reveal the condition of the transmission.
|
1.
|
Put chocks under all 4 wheels.
|
|
2.
|
Apply the handbrake fully.
|
|
3.
|
Remove the test plug (for B5) on the transmission housing and connect an oil pressure gauge.
|
|
4.
|
Press the brake pedal down hard.
|
|
5.
|
Start the engine and check the idling speed (825 rpm).
|
|
6.
|
Depress the foot brake fully and place the selector lever in positions D and R respectively and check the system pressure according to the table.
Position
|
Idling
|
Stalling speed
|
D
|
3.4-3.9 bar
|
13.1-14.2bar
|
R
|
5.1 - 6.2 bar
|
17.4 - 20.2 bar
|
|
Important
|
|
Do not run for longer than 5 seconds when testing as the oil temperature can rise above the permitted level. Wait at least 1 minute between tests.
|
|
|
Check that no leakage occurs when the oil pressure gauge is connected.
Result of the hydraulic test
|
Cause of fault
|
Higher pressure than shown above in both "D" and "R"
|
- Fault in solenoid SLT
- Fault in the voltage supply to the valves
|
Lower pressure than shown above in both "D" and "R"
|
- Fault in solenoid SLT
- Fault in the voltage supply to the valves
- Fault in the transmission fluid pump
- Fault in brake B5
- oil leak in the "D" or "R" hydraulic circuits
|
Lower pressure than shown above only in "D"
|
- too low system pressure
- Fault in clutch C1
|
Lower pressure than shown above only in "R"
|
- Fault in the "R" hydraulic circuit
- Fault in clutch C2
- Fault in brake B3
|
|
