2004 DAEWOO LACETTI ACC

5A1 – 78IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P0604
INTERNAL CONTROL MODULE RANDOM ACCESS
MEMORY(RAM) ERROR
Circuit Description
A normal function of the Transmission Control Module
(TCM) programming is to perform an internal check that
verifies the integrity of the RAM memory allocations.
The DTC P0604 sets when the Random Access
Memory(RAM) is not operating correctly when checked on
initialization. An area of RAM is failed a read/ write test.
Conditions For Setting The DTC
S An area of RAM is failed a read/ write test.
S System voltage is too high or too low.
S Transaxle input voltage is too high or too low.
S Immediately after the above condition occurs.
Action Taken When The DTC Sets
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 by hydraulic control.
S After ignition OFF/ON : 3rd gear by hydraulic con-
trol. Possible P, R and N also possible.
S Power supply cut off to the EDS valve.
Conditions For Clearing The MIL/DTC
S The MIL will turn OFF when the malfunction has
not occurred after three–ignition cycle.
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 P0604 sets, the replacement of TCM is
recommended.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 79
DAEWOO V–121 BL4
DTC P0604 – Internal Control Module Random Access
Memory(RAM) Error
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
Does the scan tool display P0604?–Go to Step 3Go to ”Diag-
nostic Aids”
31. Turn the ignition OFF.
2. Replace the TCM.
Is the action complete?–Go to Step 4–
41. Using the scan tool, clear the DTCs.
2. Road test the vehicle within the conditions for
setting this DTC as specified in the text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 5Go to Step 2
51. Check if any DTCs are set.
2. Are any DTCs displayed that have not been
diagnosed?–Go to ”Applica-
ble DTC table”System OK

5A1 – 124IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0781
1–2 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 126IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0782
2–3 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 128IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P0783
3–4 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
–The transaxle can be of more compact design and
is lighter on account of the absence of freewheels
and the lower number of shift elements.–Lower drag losses, i.e. higher efficiency.
–Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting The DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 130IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1604
DATA CHECK OF INTERNAL & EXTENDED RAM FAILED
Circuit Description
A normal function of the Transmission Control Module
(TCM) programming is to perform an internal check that
verifies the integrity of the RAM memory allocations.
The DTC P1604 sets when the Random Access
Memory(RAM) is not operating correctly when checked on
initialization. An area of RAM is failed a read/ write test.
Conditions for Setting The DTC
S An area of RAM is failed a read/ write test.
S System voltage is too high or too low.
S Transaxle input voltage is too high or too low.
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 by hydraulic control.
S After ignition OFF/ON : 3rd gear by hydraulic con-
trol. Possible P, R and N also possible.
S Power supply cut off to the EDS valve.
Conditions for Clearing the MIL/DTC
The MIL will turn OFF when the malfunction has not oc-
curred after three–ignition cycle.
A history DTC will clear after 40 consecutive warm up
cycles without a fault.
Using a scan tool can clear history DTCs.
Diagnostic Aids
S When DTC P1604 sets, the possible cause of fault
could be TCM.

5A1 – 180IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P1881
2–1 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are 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 torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting the DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not in N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 182IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P1883
3–2 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are 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 torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting the DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not in N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.