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.
5A1 – 42IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
GEAR SHIFT CONTROL
1. Selector Control Lever
2. Gear Shift Knob
3. Cover
4. Step Gate Slider
5. BTSI Button
6. Spring7. Positioning Spring
8. Solenoid
9. Base Plate
10. T/A Lever
11. Select Cable
12. Cable Fastener
5A1 – 44IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
4. Repair vehicle, if necessary.
Inspect:
S Fluid level.
S Manual linkage.
Install or Connect:
S Scan tool (scanner)
S Oil pressure gauge at line pressure port (clutch B or
E ports on transaxle case)
5. Put gear selector in Park and set the parking brake.6. Start engine and allow it to warm up at idle.
7. Access the ”Solenoid 1 Control Mode” on the scan-
ner.
8. Switching solenoid 1 ON/OFF, accelerating the en-
gine to 2,500rpm, and then read the line pressure
at the each gear.
9. Compare data to the Drive–Park–Neutral line pres-
sure chart below.
Notice : Total test running time should not exceed 2 min-
utes, or transaxle damage could occur.
CAUTION : Brake must be applied at all times to pre-
vent unexpected vehicle motion.
If pressure readings differ greatly from the line pressure
chart, refer to the Diagnosis Charts contained in this sec-
tion.
Notice : Clutch damage may occur.
The scanner is only able to control the pressure control so-
lenoid in Park and Neutral with the vehicle stopped.
This protects the clutches from extremely high or low pres-
sures in Drive or Reverse rang.
Gear Range
SolenoidLine
Pressure B PortE Port
Park / NeutralONLOW90~124.7 psi (6.2~8.6 bar)
OFFHIGH221.9~252.3 ps
i (15.3~17.4 bar)
ReverseONLOW90~124.7 psi (6.2~8.6 bar)
OFFHIGH221.9~252.3 psi
(15.3~17.4 bar)
DriveONLOW90~124.7 psi (6.2~8.6 bar)
OFFHIGH137.7~162.4 psi
(9.5~11.2 bar)
3ONLOW90~124.7 psi (6.2~8.6 bar)90~124.7 psi (6.2~8.6 bar)
OFFHIGH221.9~252.3 psi
(15.3~17.4 bar)137.7~162.4 psi
(9.5~11.2 bar)
2ONLOW90~124.7 psi (6.2~8.6 bar)
OFFHIGH137.7~162.4 psi
(9.5~11.2 bar)
1ONLOW90~124.7 psi (6.2~8.6 bar)
OFFHIGH221.9~252.3 psi
(15.3~17.4 bar)
ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 47
DAEWOO V–121 BL4
Repairing the Fluid Leak
Once the leak point is found the source of the leak must
be determined. The following list describes the potential
causes for the leak:
S Fasteners are not torqued to specification.
S Fastener threads and fastener holes are dirty or
corroded.
S Gaskets, seals or sleeves are misarranged, dam-
aged or worn.
S Damaged, warped or scratched seal bore or gasket
surface.
S Loose or worn bearing causing excess seal or
sleeve wears.
S Case or component porosity.
S Fluid level is too high.
S Plugged vent or damaged vent tube.
S Water or coolant in fluid.
S Fluid drain back holes plugged.
ELECTRICAL/GARAGE SHIFT TEST
This preliminary test should be performed before a hoist
or road test to make sure electronic control inputs is con-
nected and operating. If the inputs are not checked before
operating the transaxle, a simple electrical condition could
be misdiagnosed as a major transaxle condition.
A scan tool provides valuable information and must be
used on the automatic transaxle for accurate diagnosis.
1. Move gear selector to P (Park) and set the parking
brake.
2. Connect scan tool to Data Link Connector (DLC)
terminal.
3. Start engine.
4. Turn the scan tool ON.
5. Verify that the appropriate signals are present.
These signals may include:
S ENGINE SPEED
S VEHICLE SPEED
S THROTTLE POSITION
S TRANSAXLE GEAR STATE
S GEAR SHIFT LEVER POSITION
S TRANSAXLE FLUID TEMPERATURE
S CLOSED THROTTLE POSITION LEARN
S OPEN THROTTLE POSITION LEARNT
S CLOSED ACCEL. PEDAL POSITION LEARNT
S OPEN ACCEL. PEDAL POSITION LEARNT
S A/C COMPRESSOR STATUS
S MODE SWITCH
S THROTTLE POSITION VOLTAGE
S GEAR SHIFT LEVER POSITION VOLTAGE
S TRANS. FLUID TEMPERATURE VOLTAGE
S A/C SWITCH
S MODE SWITCH VOLTAGE
S BATTERY VOLTAGE
6. Monitor the A/C COMPRESSOR STATUS signal
while pushing the A/C switch.S The A/C COMPRESSOR STATUS should come
ON when the A/C switch is pressed, and turns
OFF when the A/C switch is repushed.
7. Monitor the GEAR SHIFT LEVER POSITION signal
and move the gear shift control lever through all the
ranges.
S Verify that the GEAR SHIFT LEVER POSITION
value matches the gear range indicated on the
instrument panel or console.
S Gear selections should be immediate and not
harsh.
8. Move gear shift control lever to neutral and monitor
the THROTTLE POSITION signal while increasing
and decreasing engine speed with the accelerator
pedal.
S THROTTLE POSITION should increase with
engine speed.
ROAD TEST PROCEDURE
S Perform the road test using a scan tool.
S This test should be performed when traffic and road
conditions permit.
S Observe all traffic regulations.
The TCM calculates upshift points based primarily on two
inputs : throttle angle and vehicle speed. When the TCM
wants a shift to occur, an electrical signal is sent to the shift
solenoids which in turn moves the valves to perform the
upshift.
The shift speed charts reference throttle angle instead of
”min throttle” or ”wot” to make shift speed measurement
more uniform and accurate. A scan tool should be used to
monitor throttle angle. Some scan tools have been pro-
grammed to record shift point information. Check the
introduction manual to see if this test is available.
Upshift Procedure
With gear selector in drive(D)
1. Look at the shift speed chart contained in this sec-
tion and choose a percent throttle angle of 10 or
25%.
2. Set up the scan tool to monitor throttle angle and
vehicle speed.
3. Accelerate to the chosen throttle angle and hold the
throttle steady.
4. As the transaxle upshifts, note the shift speed and
commanded gear changes for :
S Second gear.
S Third gear.
S Fourth gear.
Important : Shift speeds may vary due to slight hydraulic
delays responding to electronic controls. A change from
the original equipment tire size affects shift speeds.
Note when TCC applies. This should occur in fourth gear.
If the apply is not noticed by an rpm drop, refer to the
”Lock–up Clutch Diagnosis” information contained in this
section.
5A1 – 48IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
The Lock up clutch should not apply unless the transaxle
has reached a minimum operating temperature of 8°C
(46°F) TRANS TEMP AND engine coolant temp of 50°C
(122°F).
5. Repeat steps 1–4 using several different throttle
angles.
Part Throttle Detent Downshift
At vehicle steeds of 55 to 65km/h (34 to 40mph) in Fourth
gear, quickly increase throttle angle to greater than 50%.
Verify that :
S TCC apply.
S Transaxle downshift to 3rd gear.
S Solenoid 1 turns ON to OFF.
S Solenoid 2 turns OFF.
Full Throttle Detent Downshift
At vehicle speeds of 55 to 65km/h (34 to 40mph)in Fourth
gear, quickly increase throttle angle to its maximum posi-
tion (100%)
Verify that :
S TCC release.
S Transaxle downshift to Second gear immediately.
S Solenoid 1 turns ON to OFF
S Solenoid 2 turns OFF.
Manual Downshifts
1. At vehicle speeds of 60km/h (40mph)in Fourth
gear, release accelerator pedal while moving gear
selector to Manual Third (3). Observe that :
S Transaxle downshift to Third gear immediately.
S Engine slows vehicle down.
2. Move gear selector back to overdrive(D) and accel-
erate to 31mph (50km/h). Release the accelerator
pedal and move the gear selector to Manual
First(1) and observe that :
S Transaxle downshift to second gear immediate-
ly.
S Engine slows vehicle down
Notice : A Manual First––Third Gear Ratio will occur at
high speeds as an upshift safety feature. Do not attempt
to perform this shift.
Coasting Downshifts
1. With the gear selector in Overdrive(D), accelerate
to Fourth gear with TCC applied.
2. Release the accelerator pedal and lightly apply the
brakes, and observe that :
S TCC release.
S Down shifts occur at speeds shown ON the shift
speed chart.
Manual Gear Range Selection
Upshifts in the manual gear ranges are controlled by the
shift solenoids. Perform the following tests by accelerating
at 25 percent TP sensor increments.
Manual Third (3)
S With vehicle stopped, move the gear selector to
Manual third(3) and accelerate to observe :
– 1–2 shift.
– 2–3 shift.
Manual Second (2)
S With vehicle stopped, move the gear selector to
Manual second(2) and accelerate to observe :
– 1–2 shift.
S Accelerate to 40km/h(25mph) and observe :
– 2–3 shift does not occur
– TCC does not apply
Manual First (1)
S With vehicle stopped, move gear selector to Manu-
al First(1). Accelerate to 30km/h(19mph) and ob-
serve :
– No upshifts occur
Reverse (R)
S With vehicle stopped, move gear selector to R(Re-
verse) and observe :
– Solenoid 1 is OFF
– Solenoid 2 is OFF
Use a scan tool to see if any transaxle trouble codes have
been set. Refer to ”Diagnostic Trouble Codes”in this sec-
tion and repair the vehicle as directed. After repairing the
vehicle, perform the hoist test and verify that the code has
not set again.
If the transaxle is not performing well and no trouble codes
have been set, there may be an intermittent condition.
Check all electrical connections for damage or a loose fit.
You also have to perform a snapshot test which can help
catch an intermittent condition that dose not occur long
enough to set a code.
You may want to read ”Electronic Component Diagnosis”
in this section to become familiar with transaxle conditions
caused by transaxle electrical malfunction.
If no trouble codes have been set and the condition is sus-
pected to be hydraulic, take the vehicle on a road test.
TORQUE CONVERTER LOCK–UP
CLUTCH(TCC) DIAGNOSIS
To properly diagnosis the lock–up clutch(TCC) system,
perform all electrical testing first and then the hydraulic
testing.
The TCC is applied by fluid pressure which is controlled by
a solenoid Located inside the valve body. The solenoid is
energized by completing an electrical circuit through a
combination of switches and sensors.
ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 49
DAEWOO V–121 BL4
Functional Check Procedure
Inspect
1. Install a tachometer or scan tool.
2. Operate the vehicle unit proper operating tempera-
ture is reached.
3. Drive the vehicle at 80 to 88km/h (50 to 55 mph)
with light throttle(road load).
4. Maintaining throttle position, lightly touch the brake
pedal and check for release of the TCC and a slight
increase in engine speed(rpm).
5. Release the brake slowly accelerate and check for
a reapply of the Lock up clutch and a slight de-
crease in engine speed(rpm).
Torque Converter Evaluation
Torque Converter Stator
The torque converter stator roller clutch can have one of
two different type malfunctions :
A. Stator assembly freewheels in both directions.
B. Stator assembly remains Locked up at all times.
Condition A – Poor Acceleration Low
Speed
The car tends to have poor acceleration from a stand still.
At speeds above 50 to 55km/h(30 to 35mph), the car may
act normal. If poor acceleration is noted, it should first be
determined that the exhaust system is not blocked, and
the transaxle is in 1st(First) gear when starting out.
If the engine freely accelerates to high rpm in N(Neutral),
it can be assumed that the engine and exhaust system are
normal. Checking for poor performance in ”Drive” and ”Re-
verse” will help determine if the stator is freewheeling at all
times.
Condition B – Poor Acceleration High
Speed
Engine rpm and car speed limited or restricted at high
speeds. Performance when accelerating from a standstill
is normal. Engine may overheat. Visual examination of the
converter may reveal a blue color from overheating.
If the converter has been removed, the stator roller clutch
can be checked by inserting two fingers into the splined in-
ner race of the roller clutch and trying to turn freely clock-
wise, but not turn or be very difficult to turn counter clock-
wise.
Noise
Torque converter whine is usually noticed when the ve-
hicle is stopped and the transaxle is in ”Drive” or ”Re-
verse”. The noise will increase when engine rpm is in-
creased. The noise will stop when the vehicle is moving or
when the torque converter clutch is applied because both
halves of the converter are turning at the same speed.
Perform a stall test to make sure the noise is actually com-
ing from the converter :1. Place foot on brake.
2. Put gear selector in ”Drive”.
3. Depress accelerator to approximately 1200rpm for
no more than six seconds.
Notice : If the accelerator is depressed for more than six
seconds, damage to the transaxle may occur.
A torque converter noise will increase under this load.
Important : This noise should not be confused with pump
whine noise which is usually noticeable in P (Park), N
(Neutral) and all other gear ranges. Pump whine will vary
with pressure ranges.
The torque converter should be replaced under any of the
following conditions:
S External leaks in the hub weld area.
S Converter hub is scored or damaged.
S Converter pilot is broken, damaged or fits poorly
into crankshaft.
S Steel particles are found after flushing the cooler
and cooler lines.
S Pump is damaged or steel particles are found in the
converter.
S Vehicle has TCC shudder and/or no TCC apply.
Replace only after all hydraulic and electrical diag-
noses have been made.(Lock up clutch material
may be glazed.)
S Converter has an imbalance which cannot be cor–
rected. (Refer To Converter Vibration Test Proce-
dure.)
S Converter is contaminated with engine coolant con-
taining antifreeze.
S Internal failure of stator roller clutch.
S Excess end play.
S Heavy clutch debris due to overheating (blue con-
verter).
S Steel particles or clutch lining material found in fluid
filter or on magnet when no internal parts in unit are
worn or damaged(indicates that lining material
came from converter).
The torque converter should not be replace if :
S The oil has an odor, is discolored, and there is no
evidence of metal or clutch facing particles.
S The threads in one or more of the converter bolt
holes are damaged.
–correct with thread insert.
S Transaxle failure did not display evidence of dam-
age or worn internal parts, steel particles or clutch
plate lining material in unit and inside the fluid filter.
S Vehicle has been exposed to high mileage(only).
The exception may be where the Lock up clutch
damper plate lining has seen excess wear by ve-
hicles operated in heavy and/or constant traffic,
such as taxi, delivery or police use.
Lock–Up Clutch Shudder Diagnosis
The key to diagnosing lock–up clutch(TCC) shudder is to
note when it happens and under what conditions.
ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 57
DAEWOO V–121 BL4
Symptom ActionPossible Cause
Sealing Ring Selector ShaftS Check sealing ring.
S Replace sealing ring as described in the repair
instruction.
O–ring at Socket OutletS Check O–ring.
S Replace O–ring as described in the repair in-
struction.
O–ring and Speed Sensor ConnectionS Check O–ring.
S Replace O–ring as described in the repair in-
struction.
Oil Leak Incorrectly IdentifiedS No oil leak is possible at this point.
Speed Sensor Itself Is LeakingS Check speed sensor.
S Replace speed sensor as described in the re-
pair instruction.
Hair Line Crack at the Piping in the Con-
nection Area, Sealing Ring Fit in Trans-
axle HousingS Pressurize the line with compressed air and
check it.
S Replace lines as described in the repair in-
struction.
O–ring Defective, IncorrectCheck O–ring.
Replace O–rings as described in the repair instruc-
tion.
Plug LooseCheck the Tightening Torque for the screw plug.
Tighten to torque specified in the repair instruction.
Noise
SymptomPossible CauseAction
NoiseTFT Level Too LowS When the TFT level is too low, the gear wheels
from the transaxle oil pump might generate
noise.
S Check the TFT level as described in the repair
instruction and fill to the proper level.
Monolith in Catalytic Converter Has
BrokenS Check according to the exhaust gas diagnostic
procedure or by shaking the catalytic converter
casing.
S Replace catalytic converter if necessary.
Noise from Auxiliaries (e.g. exhaust
system, alternator, drive shafts.)S Check these components; if necessary, elimi-
nate the faults as described in the repair in-
struction
Noise from Tires or Wheel BearingsS Eliminate fault if necessary
Noise from Planetary GearsS Whistling noise on traction and overrun(in first
gear only)caused by high rotating speeds(func-
tionally unavoidable)
Cumulative Tooth Backlash in the Com-
plete Drive LineS Production status. Customer must be con-
vinced.
Jerky Noise of the Parking Lock (e.g.
when the car is standing on a gradient)S Load–reversal reaction
S Apply the handbrake before selection the park-
ing Lock (position P)
5A1 – 86IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P0705
TRANSMISSION RANGE SENSOR CIRCUIT
MALFUNCTION (PRNDL INPUT)
Circuit Description
The Transmission range switch is located on the selector
shaft and informs the TCM of the current selector lever
position P–R–N–D–3–2–1.
The selector lever position is transmitted to the TCM in en-
coded form along 4 lines. The encoding is such that mal-
functions in the connecting lead are identified.
The TR switch is located on the selector shaft, which is
connected to the selector lever via a pull cable. In addition,
the TR switch controls the starter interlock, the reverse
lights and the selector lever position indicator on the in-
strument panel.
Conditions for Setting The DTC
S TR switch stuck to closed.
S TR switch wiring harness shortage to ground.
S TR switch wiring harness shortage to power.
S Immediately after the above condition occurs.Action Taken When The DTC Sets
S The Malfunction Indicator Lamp(MIL) will illuminate.
S The TCM will record operating conditions at the
time the diagnostic fails. This information will be
stored in the Failure Records buffer.
S Adopt Emergency/ Substitute mode and constant
4th gear.
Conditions for Clearing the MIL/DTC
S The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycles.
S A history DTC will clear after 40 consecutive warm
up cycles without a fault.
S Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P0705 sets, the possible cause of TR
switch.