PRE-RELEASE
Solenoid valves, S1-S5 for gear changing
| Solenoid valves, S1-S5 for gear changing |
The five solenoid valves S1-S5 are mounted in the valve housing which is mounted on the transmission. The solenoid valves control the gear change valves by switching on and off the oil flow to the respective valves.
The solenoids are directly grounded via their casings to the valve housing and the control module operates each solenoid by switching on and off their respective B+ voltage supply. S1, S2, and S4 are closed when energized whilst S3 and S5 are open when energized. Solenoid S1 is connected to control module pin 34 (B), Solenoid S2 is connected to control module pin 24 (B), Solenoid S3 is connected to control module pin 8 (B), Solenoid S4 is connected to control module pin 14 (B) and Solenoid S5 is connected to control module pin 13 (B).
The control module activates the appropriate valve for upshifting or downshifting depending on the input/output speed, accelerator position and selected driving programme.
The operation of the solenoids with respect to the gear positions is as follows:
|
Gear position
|
S1
|
S2
|
S3
|
S4
|
S5
|
|
P
|
OFF
|
OFF
|
OFF
|
OFF
|
OFF
|
|
R ≤ 7 km/h
|
OFF
|
OFF
|
ON
|
OFF
|
ON
|
|
R > 7 km/h
|
0ON
|
OFF
|
OFF
|
OFF
|
OFF
|
|
N
|
OFF
|
OFF
|
OFF
|
OFF
|
OFF
|
|
D, M, 5
|
OFF
|
OFF
|
OFF
|
ON
|
OFF
|
|
D, M, 4
|
OFF
|
ON
|
OFF
|
ON
|
OFF
|
|
D, M, 3
|
OFF
|
ON
|
ON
|
ON
|
OFF
|
|
D, M, 2
|
OFF
|
ON
|
ON
|
OFF
|
OFF
|
|
D, M, 1
|
ON
|
OFF
|
ON
|
OFF
|
ON for engine braking
|
0 = OFF = 0V, 1 = ON = B+
The nominal resistance of the windings in solenoid S1 is nominally 12-16 Ω at 20°C and in solenoids S2-S5 nominally 11-15 Ω at 20°C.
Diagnostics
Diagnostic trouble code P0773 will be generated in the event of a fault in solenoid S1.Diagnostic trouble code P0753 will be generated in the event of a fault in solenoid S2.
Diagnostic trouble code P0758 will be generated in the event of a fault in solenoid S3.
Diagnostic trouble code P0763 will be generated in the event of a fault in solenoid S4.
Diagnostic trouble code P0768 will be generated in the event of a fault in solenoid S5.
In all cases the transmission goes into the limp-home mode.
