SECTION : 5A1
ZF 4 HP 16 AUTOMATIC TRANSAXLE
CAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool
or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help
prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.
TABLE OF CONTENTS
INTRODUCTION5A1–3 . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZF 4HP 16 Automatic Transaxle 5A1–3. . . . . . . . . . . .
Transaxle Components 5A1–4. . . . . . . . . . . . . . . . . . . .
SPECIFICATIONS5A1–5 . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 5A1–5. . . . . . . . . . . . . . . . . . . .
Transaxle Gear Ratio 5A1–5. . . . . . . . . . . . . . . . . . . . . .
Fluid Capacity 5A1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 5A1–5. . . . . . . . . .
Shift Speed Chart 5A1–7. . . . . . . . . . . . . . . . . . . . . . . . .
Line Pressure 5A1–8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS5A1–9 . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools Table 5A1–9. . . . . . . . . . . . . . . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS5A1–11 . . .
Transaxle Control Module (1 of 2) 5A1–11. . . . . . . . . .
Transaxle Control Module (2 of 2) 5A1–12. . . . . . . . . .
Shift Mode Diagram 5A1–13. . . . . . . . . . . . . . . . . . . . . .
Power Flow Diagram 5A1–17. . . . . . . . . . . . . . . . . . . . .
COMPONENT LOCATOR5A1–33 . . . . . . . . . . . . . . . . . .
Transaxle Identification Information 5A1–33. . . . . . . .
Torque Converter 5A1–34. . . . . . . . . . . . . . . . . . . . . . . .
Transaxle Housing 5A1–35. . . . . . . . . . . . . . . . . . . . . . .
Oil Pump 5A1–36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Cover & Oil Pan Cover 5A1–37. . . . . . . . . . . . . .
Parking Lever 5A1–38. . . . . . . . . . . . . . . . . . . . . . . . . . .
Input Shaft & Shift Gear 5A1–39. . . . . . . . . . . . . . . . . .
Valve Body 5A1–41. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gear Shift Control 5A1–42. . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSTIC INFORMATION AND PROCEDURES
DIAGNOSIS5A1–43 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Basic Knowledge Required 5A1–43. . . . . . . . . . . . . . . .
Functional Check Procedure 5A1–43. . . . . . . . . . . . . .
Line Pressure Check Procedure 5A1–43. . . . . . . . . . .
Clutch Plate Diagnosis 5A1–45. . . . . . . . . . . . . . . . . . .
Cooler Flushing and Flow Test 5A1–45. . . . . . . . . . . . . Transaxle Fluid Level Service Procedure 5A1–45. . . .
Electrical/Garage Shift Test 5A1–47. . . . . . . . . . . . . . .
Road Test Procedure 5A1–47. . . . . . . . . . . . . . . . . . . . .
Torque Converter Lock–Up Clutch(TCC)
Diagnosis 5A1–48. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TCM Initialization Procedure 5A1–50. . . . . . . . . . . . . .
Shift Speed Chart 5A1–51. . . . . . . . . . . . . . . . . . . . . . . .
Internal Wiring Harness Check 5A1–51. . . . . . . . . . . .
Transaxle Wiring Harness Connector 5A1–54. . . . . . .
Symptom Diagnosis 5A1–56. . . . . . . . . . . . . . . . . . . . . .
DIAGNOSTIC TROUBLE CODE DIAGNOSIS5A1–60
Diagnostic Trouble Code (DTC) Identification 5A1–60
DTC P0562 – System Voltage Low 5A1–68. . . . . . . . .
DTC P0563 – System Voltage High 5A1–71. . . . . . . .
DTC P0601 – Internal Control Module Memory
Checksum Error 5A1–74. . . . . . . . . . . . . . . . . . . . . . .
DTC P0603 – Internal Control Module Keep
Alive Memory(KAM) Error 5A1–76. . . . . . . . . . . . . . .
DTC P0604 – Internal Control Module Random
Access Memory(RAM) Error 5A1–78. . . . . . . . . . . . .
DTC P0606 – Transaxle Control Module
Processor Fault 5A1–80. . . . . . . . . . . . . . . . . . . . . . . .
DTC P0703 – Brake Switch Circuit
Malfunction 5A1–83. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0705 – Transmission Range Sensor
Circuit Malfunction(PRNDL Input) 5A1–86. . . . . . . .
DTC P0710 – Transmission Fluid Temperature
Sensor Circuit Malfunction 5A1–89. . . . . . . . . . . . . .
DTC P0715 – Input Speed Sensor(ISS) Circuit
Malfunction 5A1–92. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0716 – Input Speed Sensor(ISS) Circuit
Range/Performance 5A1–95. . . . . . . . . . . . . . . . . . . .
DTC P0717 – Input Speed Sensor(ISS) Circuit
No Signal 5A1–98. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0720 – Output Speed Sensor(OSS)
Circuit Malfunction 5A1–101. . . . . . . . . . . . . . . . . . . .
DTC P0721 – Output Speed Sensor(OSS)
Circuit Range/Performance 5A1–104. . . . . . . . . . . . .
5A1 – 2IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DTC P0722 – Output Speed Sensor(OSS)
Circuit No Signal 5A1–107. . . . . . . . . . . . . . . . . . . . . .
DTC P0725 – Engine Speed Input Circuit
Malfunction 5A1–110. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0726 – Engine Speed Input Circuit
Range/Performance 5A1–112. . . . . . . . . . . . . . . . . . .
DTC P0727 – Engine Speed Input Circuit No
Signal 5A1–114. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0731 – Gear 1 Incorrect Ratio 5A1–116. . . . . .
DTC P0732 – Gear 2 Incorrect Ratio 5A1–118. . . . . .
DTC P0733 – Gear 3 Incorrect Ratio 5A1–120. . . . . .
DTC P0734 – Gear 4 Incorrect Ratio 5A1–122. . . . . .
DTC P0781 – 1–2 Shift Malfunction 5A1–124. . . . . . .
DTC P0782 – 2–3 Shift Malfunction 5A1–126. . . . . . .
DTC P0783 – 3–4 Shift Malfunction 5A1–128. . . . . . .
DTC P1604 – Data Check of Internal &
Extended Ram Failed 5A1–130. . . . . . . . . . . . . . . . . .
DTC P1606 – Failure Of External Watchdog 5A1–132
DTC P1671 – CAN Transmit Message
Failure 5A1–134. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1672 – CAN Bus Off Failure 5A1–136. . . . . . . .
DTC P1673 – CAN Receive ECM Message
Failure 5A1–138. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1839 – EDS 3 Output Shorted To
Ground 5A1–140. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1840 – EDS 3 Output Shorted To
Power 5A1–142. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1841 – EDS 3 Output Open 5A1–144. . . . . . . .
DTC P1850 – Solenoid 1 Output Shorted To
Ground 5A1–146. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1851 – Solenoid 1 Output Shorted To
Power 5A1–148. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1852 – Solenoid 1 Output Open 5A1–150. . . .
DTC P1853 – Solenoid 2 Output Shorted To
Ground 5A1–152. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1854 – Solenoid 2 Output Shorted To
Power 5A1–154. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1855 – Solenoid 2 Output Open 5A1–156. . . .
DTC P1861 – EDS 4 Output Shorted To
Ground 5A1–158. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1862 – EDS 4 Output Shorted To
Power 5A1–160. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1863 – EDS 4 Output Open 5A1–162. . . . . . . .
DTC P1864 – EDS 5 Output Shorted To
Ground 5A1–164. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1865 – EDS 5 Output Shorted To
Power 5A1–166. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1866 – EDS 5 Output Open 5A1–168. . . . . . . .
DTC P1867 – EDS 6 Output Shorted To
Ground 5A1–170. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DTC P1868 – EDS 6 Output Shorted To
Power 5A1–172. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1869 – EDS 6 Output Open 5A1–174. . . . . . . .
DTC P1871 – EDS Valve Power Supply
Circuit Shorted to Power 5A1–176. . . . . . . . . . . . . . .
DTC P1874 – Solenoid Valve Power Supply
Circuit Shorted to Power 5A1–178. . . . . . . . . . . . . . .
DTC P1881 – 2–1 Shift Malfunction 5A1–180. . . . . . .
DTC P1883 – 3–2 Shift Malfunction 5A1–182. . . . . . .
DTC P1884 – 4–3 Shift Malfunction 5A1–184. . . . . . .
DTC P1885 – 3–1 Shift Malfunction 5A1–186. . . . . . .
DTC P1886 – 4–2 Shift Malfunction 5A1–188. . . . . . .
MAINTENANCE AND REPAIR5A1–190 . . . . . . . . . . . .
ON–VEHICLE SERVICE 5A1–190. . . . . . . . . . . . . . . . . .
Transaxle Fluid Level Checking Procedure 5A1–190.
Changing the Fluid 5A1–191. . . . . . . . . . . . . . . . . . . . . .
Fluid Level Set After Service 5A1–192. . . . . . . . . . . . .
Repairing Fluid Leaks 5A1–192. . . . . . . . . . . . . . . . . . .
Case Porosity Repair 5A1–193. . . . . . . . . . . . . . . . . . . .
Shift Control Lever Assembly 5A1–193. . . . . . . . . . . . .
Shift Control Cable 5A1–195. . . . . . . . . . . . . . . . . . . . . .
Shift Control Cable Adjustment 5A1–196. . . . . . . . . . .
Transaxle Control Module(TCM) 5A1–197. . . . . . . . . .
Park/Neutral Start Switch 5A1–198. . . . . . . . . . . . . . . .
Oil Cooler Pipes/Hoses 5A1–199. . . . . . . . . . . . . . . . . .
Drive Axle Oil Seal 5A1–201. . . . . . . . . . . . . . . . . . . . . .
Oil Pan, Oil Pan Gasket 5A1–201. . . . . . . . . . . . . . . . .
Control Valve Body Assembly 5A1–203. . . . . . . . . . . .
Left Transaxle Mounting Bracket 5A1–205. . . . . . . . . .
Transaxle Assembly 5A1–206. . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 5A1–212. . . . . . . . . . . . . . . . . . . . . . . . . . .
Torque Converter 5A1–212. . . . . . . . . . . . . . . . . . . . . . .
Transaxle Holding Fixture Assembly 5A1–212. . . . . . .
Valve Body 5A1–212. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Cover 5A1–213. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch B/E 5A1–214. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch B/E Measurement Procedure 5A1–217. . . . . .
Planetary Gear Set 5A1–220. . . . . . . . . . . . . . . . . . . . .
Brake C/D 5A1–221. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential 5A1–224. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Side Shaft 5A1–224. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake F, Slotted Nut 5A1–225. . . . . . . . . . . . . . . . . . . . .
Torque Converter Housing 5A1–227. . . . . . . . . . . . . . .
Shift Mechanism 5A1–228. . . . . . . . . . . . . . . . . . . . . . . .
Parking Lock System 5A1–229. . . . . . . . . . . . . . . . . . . .
Bearing Plate(With Spur Gear) Assembly 5A1–229. .
Oil Pump Assembly 5A1–229. . . . . . . . . . . . . . . . . . . . .
Differential/Side Shaft Outer Race, Bearing
Shim 5A1–230. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 3
DAEWOO V–121 BL4
Important Measurement/Adjustment 5A1–230. . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION5A1–232 . . . . . . . . . . . . . . . . . . . . . . . . . . . Mechanical Components 5A1–232. . . . . . . . . . . . . . . . .
Electronical Components 5A1–236. . . . . . . . . . . . . . . .
TCM Inputs That Affect the 4HP 16
Transaxle 5A1–241. . . . . . . . . . . . . . . . . . . . . . . . . . .
INTRODUCTION
ZF 4HP 16 AUTOMATIC TRANSAXLE
The ZF 4 HP 16 is a four–speed automatic transaxle de-
signed for cars with front–wheel drive and a transversely
mounted engine.
The transaxle has a hydrodynamic torque converter with
a controlled slip lock–up clutch.
A planetary gear train establishes the mechanical gear ra-
tios. The integral constant ratio can be adapted to the en-
gine’s power output and the vehicle’s weight. The elec-
tronic–hydraulic control makes controlled power shifts and
various shift programs possible. In selector lever position
”P”, the output is locked mechanically.The special feature of this transaxle is that it operates with-
out freewheels. Shifting between individual gears takes
place by means of overlapping clutch engagement and re-
lease.
The advantage of overlap shifting is as follows:
– The transaxle can be of more compact design
and is lighter on account of the absence of free-
wheels and the lower number of shift elements
– Lower drag losses, i.e. higher efficiency
– Lower peak torques acting on the components
and driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 5
DAEWOO V–121 BL4
SPECIFICATIONS
GENERAL SPECIFICATIONS
Definition
Transaxle Type4–speed with four–wheel drive and transverse engine
Input Torque240 NSm (177 lb–ft)
Transaxle Weight76kg (168 lb)
Torque Converter Capacity9.72kg (21.4 lb)
Transaxle Fluid Type (manufacture company)ESSO LT 71141 or TOTAL ATF H50235
Transaxle Fluid Capacity7.3qt (6.9L)
TRANSAXLE GEAR RATIO
GearRatio
First2.719
Second1.487
Third1.000
Fourth0.717
Reverse 2.529
Final3.945:1
FLUID CAPACITY
LitresQuarts
Bottom Pan Removal44.2
Complete Overhaul6.97.3
Torque Converter Removal22.1
(Measurements are approximate)
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Bearing Plate Bolts23.517.5–
Slotted Nut220162–
Rear Cover Attachment Bolts23.517.5–
Baffle Plate Attachment Bolts10–89
Park/Neutral Position Switch10–89
Fluid Pump Connecting Bolts10–89
Fluid Filter Housing Cover Attachment Bolts10–89
Input Speed sensor Attachment Bolts8–71
Output Speed Sensor Attachment Bolts8–71
Valve Body Bolts8–71
Valve Body Upper & Lower Fixing Bolts6–53
Fluid Pan Connecting Bolts6–53
Fluid Pan Drain Plug4533–
5A1 – 6IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Application Lb–InLb–Ft NSm
Fluid Level Plug4533–
Line Pleasure Plugs2015–
Valve Housing 1 Cover Attachment Bolts6–53
Solenoid Valve Attachment Bolts6–53
Pressure Control Regulator(EDS) Attachment Bolts6–53
Oil Cooler Inlet Pipe Bolts3526–
Oil Cooler Outlet Pipe Bolts3526–
Shift Control Cable Adjuster Pinch Nut8–71
Shift Control Cable Attachment Nut8–71
Upper Transaxle–to–Engine Bolts7555–
Selector Lever(On Transaxle Case)1511–
Torque Converter Attachment Bolts4533–
Shift Control Assembly Mounting Bolt, Nut8–71
Lower Engine–to–Transaxle Bolts(a)7555–
Lower Engine–to–Transaxle Bolt(b)2115–
Lower Engine–to–Transaxle Bolts(c)3123–
Rear Transaxle Mounting Bracket Bolts6245–
Damping Block Connection Bolt and Nut6850–
Left Transaxle Mount Bracket Cage Bolt(a)11 081–
Left Transaxle Mount Bracket Cage Bolt(b)6548–
Left Transaxle Mount Bracket Cage Nut(c)6548–
Left Transaxle Mounting Bolts4835–
5A1 – 18IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Park/Neutral
In Park or Neutral with the engine running there is no drive
to the planetary gear set. Line pressure (from the oil pump)
is supplied to the valve body. Only clutch B is supplied and
the torque converter is released.
Control
Line Pressure Control Valve
The line pressure control valve sets the general pressure
level in the valve body. When gearshifts are not taking
place, the line pressure varies between two levels, de-
pending on the turbine torque. Line pressure increase lin-
early by time. But it has a limit point. When pressure reach-
es that point, excess oil pressure drains back into the oil
sump.
Reduction Valve
The reduction valve reduces the line pressure with which
the downstream solenoid valves and pressure control so-
lenoid valves (EDS) are supplied. This makes it possible
to use smaller solenoid valves.
The line pressure comes from the oil pump and flows to the
reduction valve. The inlet port to the reduction valve will be
blocked and line pressure will be maintained at the ap-
propriate level.
Solenoid Valve 1, 2
Solenoid Valve 1 controls the line pressure (high and low)
to the clutch valves. Solenoid Valve 1 is either ON or OFF.
When the solenoid is turned ON the line pressure will be
low [87~116psi (6~8bar)].When the solenoid is turned
OFF the line pressure will be high [232~261psi
(16~18bar)].
Solenoid 2 controls the fluid flow to clutch valve E or the
TCC clutch valve. When solenoid 2 is ON fluid is directed
to the TCC pressure valve and if the solenoid is switched
OFF fluid will flow to the inlet at clutch valve E.The TCM monitors numerous inputs to determine the ap-
propriate solenoid state combination and transaxle gear
for the vehicle operating conditions.
In Park and Neutral solenoid valve 1 is ON. So line pres-
sure flows to the safety valve and the line pressure control
valve via the solenoid valve.
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 2 is turned ON and the line pressure control
valves 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.
5A1 – 20IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Reverse
In Reverse, transaxle drive is via the input shaft and clutch
B. The elements of this transaxle function are as follows:
S Clutch B is engaged and drives the reverse sun
gear in a clock––wise direction.
S The D band is engaged and holds the planetary
gear carrier (front & rear) stationary causing the
differential pinion to rotate clockwise.
S The differential rotates in a counterclockwise direc-
tion.
S The output shaft is driven in a counterclockwise or
reverse direction.
Control
Clutch B Engaged
The line pressure, which is supplied by the oil pump, is di-
rected to clutch B via the manual valve. The position of the
check ball will change allowing direct pressure to clutch B.
Brake D Engaged
The line pressure, which engaged clutch B, is also sup-
plied to clutch valve D.In Reverse, solenoid 1 is switched ON and EDS 4 is
switched OFF. This will cause the fluid supplied to the re-
duction valve to flow to clutch valve D via the EDS 4.
The spool of clutch valve D will be depressed allowing fluid
to pass to holding valve D.
Lock–up Clutch (TCC)
Solenoid 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.
5A1 – 22IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Drive Range – First Gear
In Drive 1, transaxle drive is via the input shaft to clutch B.
The elements of this transaxle function are as follows:
S Clutch B is engaged to drive the rear sun gear.
S The rear sun gear drives the front planetary gear
carrier clockwise.
S The rear planetary gear carrier drives the front ring
gear and front planetary gear carrier clockwise.
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.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 (TCC)
Solenoid 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.