2004 DAEWOO LACETTI Automatic

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 23
DAEWOO V–121 BL4
Drive Range – Second Gear

5A1 – 24IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Drive Range – Second Gear
In Drive 2, the transaxle drive is via the input shaft and
clutch E. The elements of this transaxle function are as fol-
lows:
S Clutch E is applied to drive the front ring gear.
S The front ring gear drives the front planetary gear
carrier.
S The front planetary gear carrier drives the differen-
tial pinion gear clockwise.
S Brake F is applied holding the front sun gear sta-
tionary.
Control
Clutch E Engaged
Solenoid 2 will be switched OFF. Line pressure, which is
supplied by the reduction valve, flows to the inlet port of
clutch valve E. Fluid will then pass through the clutch valve
and clutch E will engage.Clutch F Engaged
EDS 5 will be switched ON. The line pressure, which
passed through the reduction valve, will flow to the holding
valve and the clutch valve inlet. As a result the valve spool
is depressed.
Lock–up Clutch
Solenoid valve 2 is turned ON and the line pressure control
valve spool will be depressed. Fluid will now flow through
the torque converter pressure valve.
As a result, the oil pressure behind the converter lock–up
clutch piston and in the turbine zone is equal. The direction
of flow is through the turbine shaft and through the space
behind the piston, to the turbine chamber.
Lubrication/Cooling
The lubricating valve ensures that the converter is sup-
plied with cooling oil first if the pump rate is low. The lubri-
cating pressure valve in addition guarantees that the nec-
essary amount of cooling and lubricating oil is available via
the bypass duct.
The fluid, which is supplied from the torque converter,
flows to the cooler via the lubrication valve.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 25
DAEWOO V–121 BL4
Drive Range – Third Gear

5A1 – 26IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Drive Range – Third Gear
In Drive 3, transaxle drive is via the input shaft to clutches
B and E. The elements of this transaxle function are as fol-
lows:
S Clutches B and E are engaged to drive the rear sun
gear and rear planetary gear carrier clockwise.
S The clockwise rotation of the rear sun gear and rear
planetary gear carrier will cause the front planetary
gear to rotate in the same direction.
Control
Clutch B Engaged
In Park and Neutral solenoid valves 1 and 2 are both ON.Pressure control solenoids (EDS) 4 and 6 are also turned
ON.
When EDS 6 is ON, the fluid supplied from the reduction
valve flows to the safety valve, clutch valve B and holding
valve B. The oil that is supplied to the inlet port of the clutch
valve presses on the valve spool. Line pressure then flows
to the holding valve and check ball, engaging clutch B.
Lock–up Clutch (TCC)
Solenoid valve 2 is turned ON and the line pressure control
valve spool will be depressed. Fluid will now flow through
the torque converter pressure valve.
As a result, the oil pressure behind the converter lock–up
clutch piston and in the turbine zone is equal. The direction
of flow is through the turbine shaft and through the space
behind the piston, to the turbine chamber.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 27
DAEWOO V–121 BL4
Drive Range – Fourth Gear

5A1 – 28IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Drive Range – Fourth Gear
In Drive 4, transaxle drive is via the input shaft and
clutches E and C. The elements of this transaxle function
are as follows:
S Clutch E is engaged to drive the rear planetary gear
carrier.
S The rear planetary gear carrier drives the rear ring
gear.
S The rear ring gear carrier drives the differential
gear.
Control
Clutch E Engaged
Solenoid 2 will be switched OFF. Line pressure, which is
supplied by the reduction valve, flows to the inlet port of
clutch valve E. Fluid will then pass through the clutch valve
and clutch E will engage.Clutch C Engaged
EDS 4 will be switched OFF causing the fluid level to be
high. Line pressure will be directed to the safety valve,
clutch valve D and holding valve D. Clutch valve C and
holding valve C will engage as pressure flows through the
safety valve.
Lock–up Clutch
Solenoid valve 2 is turned ON and the line pressure control
valve spool will be depressed. Fluid will now flow through
the torque converter pressure valve.
As a result, the oil pressure behind the converter lock–up
clutch piston and in the turbine zone is equal. The direction
of flow is through the turbine shaft and through the space
behind the piston, to the turbine chamber.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 29
DAEWOO V–121 BL4
Drive Range – Fourth Gear ; Emergency/Substitute Mode

5A1 – 30IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Drive Range – Fourth Gear ;
Emergency/Substitute Mode
In Drive 4, transaxle drive is via the input shaft and
clutches E and C. The elements of this transaxle function
are as follows:
S Clutch E is engaged to drive the rear planetary gear
carrier.
S The rear planetary gear carrier drives the rear ring
gear.
S The rear ring gear carrier drives the differential
gear.Control
Clutch E Engaged
Solenoid 2 will be switched OFF. Line pressure, which is
supplied by the reduction valve, flows to the inlet port of
clutch valve E. Fluid will then pass through the clutch valve
and clutch E will engage.
Clutch C Engaged
EDS 4 will be switched OFF causing the fluid level to be
high. Line pressure will be directed to the safety valve,
clutch valve D and holding valve D. Clutch valve C and
holding valve C will engage as pressure flows through the
safety valve.