Honda Civic. Manual — part 179

Fig. 42: Hydraulic Fuel Pressure Flow Diagram (D Position - Driving In 1st
Gear)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

D Position: Shifting between 1st gear and 2nd gear

As the speed of the vehicle reaches the programmed value, the PCM turns shift
solenoid valve A ON, shift solenoid valve B remains ON, and C remains OFF. Shift
solenoid valve A pressure (SA) is applied to the right end of shift valve A and to the
left side of cut valve A. Cut valve A is moved to the right side to release 1st clutch
pressure in line pressure mode, and shift valve A is moved to the left side to switch
line pressure (5A) port to A/T clutch pressure control solenoid valve C pressure
(5C) port leading to the 1st clutch. Also shift valve A uncovers 2nd clutch pressure
(20) port leading A/T clutch pressure control solenoid valve B pressure (56) to the
2nd clutch. The 1st clutch and the 2nd clutch are engaged by the A/T clutch
pressure control solenoid valve pressure mode.

hydraulic circuit.

2008 Honda Civic LX

2006-08 TRANSMISSION Automatic Transmission - Civic (Except Hybrid)

Fig. 43: Hydraulic Fuel Pressure Flow Diagram (D Position - Shifting Between
1st Gear And 2nd Gear)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

D Position: Driving in 2nd gear

The PCM turns shift solenoid valve B OFF, shift solenoid valve A remains ON, and
C remains OFF. Shift solenoid valve B is turned OFF, and shift solenoid valve B
pressure (SB) in the right end of shift valve B and in the left end of the servo
control valve is released. Cut valve B and servo control valve are kept in the right
side by line pressure (4) even though releasing hydraulic pressure in the left end.
Shift valve B is moved to the right side to switch A/T clutch pressure control
solenoid valve B pressure (5F) port to line pressure (5D) port leading to the 2nd
clutch. 2nd clutch pressure (20) is applied to the 2nd clutch, and the 2nd clutch is
engaged by the line pressure mode.

NOTE:

When used, "left" or "right" indicates direction on the
hydraulic circuit.

2008 Honda Civic LX

2006-08 TRANSMISSION Automatic Transmission - Civic (Except Hybrid)

Fig. 44: Hydraulic Fuel Pressure Flow Diagram (D Position - Driving In 2nd
Gear)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

D Position: Shifting between 2nd gear and 3rd gear

As the speed of the vehicle reaches the programmed value, the PCM turns shift
solenoid valve A OFF, while shift solenoid valve B and C remain OFF. Shift
solenoid valve A is turned OFF, and shift solenoid valve A pressure (SA) in the
right end of shift valve A and in the left end of cut valve A is released. Even though
shift solenoid valve A pressure is released, cut valve A is kept on the right side by
line pressure (4). Shift valve A is moved to the right side to switch to the line
pressure (5G) port to the A/T clutch pressure control solenoid valve B pressure (5E)
port leading to the 2nd clutch. Also shift valve A uncovers 3rd clutch pressure (30)
port leading A/T clutch pressure control solenoid valve C pressure (5L) to the 3rd

NOTE:

When used, "left" or "right" indicates direction on the
hydraulic circuit.

2008 Honda Civic LX

2006-08 TRANSMISSION Automatic Transmission - Civic (Except Hybrid)

clutch. The 2nd and 3rd clutch are engaged by the A/T clutch pressure control
solenoid valve pressure mode.

Fig. 45: Hydraulic Fuel Pressure Flow Diagram (D Position - Shifting Between
2nd Gear And 3rd Gear)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

D Position: Driving in 3rd gear

The PCM turns shift solenoid valve CON, and shift solenoid valve A and B remain
OFF. Shift solenoid valve C pressure (SC) is applied to the right side of shift valve
C and cut valve B. Shift valve C is then moved to the left side to releasing the 2nd
clutch pressure. The 3rd clutch keeps on engaging with the A/T clutch pressure
control solenoid valve C pressure mode.

NOTE:

When used, "left" or "right" indicates direction on the
hydraulic circuit.

2008 Honda Civic LX

2006-08 TRANSMISSION Automatic Transmission - Civic (Except Hybrid)