engine controls DAEWOO LACETTI 2004 Service Repair Manual

5A1 – 112IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P0726
ENGINE SPEED INPUT CIRCUIT RANGE/PERFORMANCE
Circuit Description
The transaxle control module(TCM) is an electronic de-
vice which monitors inputs to control various transaxle
functions including shift quality and transaxle sensors,
switches, and components to process for use within its’
control program. Based on this input information, the TCM
controls various transaxle output functions and devices.
DTC’s P0725, P0726 and P0727 are related to the same
circuit. These DTC’s will not illuminate the MIL, however,
the DTC will be stored in memory.
Information transmit between TCM and ECM through the
CAN line. information is as follows :
S Engine Malfunction Signal.
S Engine Speed.
S Engine Output Torque Reduction Signal.
S Engine Coolant Temperature.
Conditions for Setting The DTC
S Gear position is D.
S The engine speed is greater than 7,000rpm.S System voltage is greater than 8.5 volts.
S Engine is running.
S No engine speed error DTCs P0727, P0725.
S CAN transmitting wiring harness shorted or open.
S TCM or ECM is defective.
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.
S Open lock up clutch.
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.

5A1 – 114IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P0727
ENGINE SPEED INPUT CIRCUIT NO SIGNAL
Circuit Description
The transaxle control module(TCM) is an electronic de-
vice which monitors inputs to control various transaxle
functions including shift quality and transaxle sensors,
switches, and components to process for use within its’
control program. Based on this input information, the TCM
controls various transaxle output functions and devices.
DTC’s P0725, P0726 and P0727 are related to the same
circuit. These DTC’s will not illuminate the MIL, however,
the DTC will be stored in memory.
Information transmit between TCM and ECM through the
CAN line. information is as follows :
S Engine Malfunction Signal.
S Engine Speed.
S Engine Output Torque Reduction Signal.
S Engine Coolant Temperature.
Conditions for Setting The DTCS When turbine speed is more than 1,500 rpm, en-
gine speed is less than 400 rpm.
S System voltage is too high or too low.
S CAN transmitting wiring harness shorted or open.
S TCM or ECM is defective.
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.
S Open lock up clutch.
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.

5A1 – 134IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1671
CAN TRANSMIT MESSAGE FAILURE
Circuit Description
The transaxle control module(TCM)is an electronic device
which monitors inputs to control various transaxle func-
tions including shift quality and transaxle sensors,
switches, and components to process for use within its’
control program. Based on this input information, the TCM
controls various transaxle output functions and devices.
Information is transmitted between the TCM and ECM
through the CAN. Information is as follows:
S Engine Malfunction Signal.
S Engine Speed.
S Engine Output Torque Reduction Signal.
S Engine Coolant Temperature.
Conditions for Setting the DTC
S System voltage is too high or too low.
S CAN transmitting wiring harness shortage or open.S TCM or ECM is defective.
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.
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.

5A1 – 136IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1672
CAN BUS OFF FAILURE
Circuit Description
The transaxle control module(TCM)is an electronic device
which monitors inputs to control various transaxle func-
tions including shift quality and transaxle sensors,
switches, and components to process for use within its’
control program. Based on this input information, the TCM
controls various transaxle output functions and devices.
Information is transmitted between the TCM and ECM
through the CAN. Information is as follows:
S Engine Malfunction Signal.
S Engine Speed.
S Engine Output Torque Reduction Signal.
S Engine Coolant Temperature.
Conditions for Setting the DTC
S System voltage is too high or too low.
S CAN transmitting wiring harness shortage or open.S TCM or ECM is defective.
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.
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.

5A1 – 138IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1673
CAN RECEIVE ECM MESSAGE FAILURE
Circuit Description
The transaxle control module(TCM) is an electronic de-
vice which monitors inputs to control various transaxle
functions including shift quality and transaxle sensors,
switches, and components to process for use within its’
control program. Based on this input information, the TCM
controls various transaxle output functions and devices.
Information is transmitted between the TCM and ECM
through the CAN. Information is as follows:
S Engine Malfunction Signal.
S Engine Speed.
S Engine Output Torque Reduction Signal.
S Engine Coolant Temperature.
Conditions for Setting the DTC
S System voltage is too high or too low.
S CAN transmitting wiring harness shortage or open.S TCM or ECM is defective.
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.
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.

AISIN AUTOMATIC TRANSAXLE 5A2 – 53
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0713
TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR
CIRCUIT HIGH INPUT
Conditions for Setting the DTC
S TCM detects that A/D value of Transmission Fluid
Temperature sensor (TFT) signal is less than 15
and the minimum A/D value is more than 943,
when it is past 15 minutes after ignition ON.(A/D
value 943 : 4.7 v)
S After 1 time of above detection.
S Gear selector position is except P and N.
S Engine revolution is 400 rpm or greater.
Action Taken When the DTC Sets
S TCM will request the illumination of MIL and store
DTC when TCM detects a failure on the first ignition
cycle.
S TCM judges the temperature of the transmission
fluid is 200°C (392°F).
S No lockup control
S No 4th gear
S No self–learning controlS No timing solenoid control N–D
Conditions for Clearing the DTC
S The TCM turns off the MIL when no further failures
detected for three consecutive ignition cycles.
S The scan tool can clear the DTC from the TCM his-
tory.
S The TCM clears the DTC from the TCM history
memory after forty consecutive warm up cycles
without fault.
S TCM detects the temperature of the transmission
fluid is between 0°C (32°F) and 150°C (302°F) for
10 seconds continuously.
Cause of Failure
S Wiring harness or connector between Transmission
Fluid Temperature (TFT) sensor and TCM
S TFT sensor
S TCM

5A2 – 56IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0717
INPUT SHAFT SPEED (ISS) SENSOR CIRCUIT NO
SIGNAL
Conditions for Setting the DTC
S This DTC detects no signal of Input Shaft Speed
(ISS) sensor circuit for a long period of time. ( Rev-
olution : 0 rpm
10000 rpm).
S TCM detects no pulse of ISS sensor while TCM
detects 4 pulses of Output Speed Sensor. This
detection 1000 times continuously.
S D,2,L range selected
S Engine revolution is 400 rpm or greater.
S DTCs P0751, P0753, P0756, P0758, and P0705
are not set.
S Output revolution is 775 rpm or greater.
S 25 seconds later after Neutral to Drive shift.
S 10 seconds later after changing the gear.
Action Taken When the DTC Sets
S TCM will request the illumination of MIL and store
DTC when TCM detects a failure on the first ignition
cycle.
S No lockup control
S No engine torque reduction controlS No engagement pressure control
S No 4th gear
S No self–learning control
S No timing solenoid control N–D
Conditions for Clearing the DTC
S The TCM turns off the MIL when no further failures
detected for three consecutive ignition cycles.
S The scan tool can clear the DTC from the TCM his-
tory.
S The TCM clears the DTC from the TCM history
memory after forty consecutive warm up cycles
without fault.
S TCM detects 250 pulses of ISS while failure detec-
tion is not achieved.
Cause of Failure
S Wiring harness or connector between Input Shaft
Speed (ISS) sensor and TCM
S ISS sensor
S TCM

AISIN AUTOMATIC TRANSAXLE 5A2 – 59
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0722
OUPUT SHAFT SPEED (OSS) SENSOR CIRCUIT NO
SIGNAL
Conditions for Setting the DTC
S This DTC detects no signal of Output Shaft Speed
(OSS) sensor circuit for a long period of time. (
Revolution : 0 rpm
10000 rpm).
S TCM detects no pulse of Output Shaft Speed
(OSS) sensor while TCM detects 178 pulses of In-
put Shaft Speed sensor. This detection 500 times
continuously.
S D,2,L range selected
S Input speed is 5 km/h (3 mph) or greater.
S DTCs P0751, P0753, P0756, P0758, P0717 and
P0705 are not set.
S 25 seconds later after Neutral to Drive shift.
Action Taken When the DTC Sets
S TCM will request the illumination of MIL and store
DTC when TCM detects a failure on the first ignition
cycle.
S No lockup control
S No engine torque reduction control
S No engagement pressure controlS No 4th gear
S No self–learning control
S No prevent reverse gear control
Conditions for Clearing the DTC
S The TCM turns off the MIL when no further failures
detected for three consecutive ignition cycles.
S The scan tool can clear the DTC from the TCM his-
tory.
S The TCM clears the DTC from the TCM history
memory after forty consecutive warm up cycles
without fault.
S TCM detects 250 pulses of Output Shaft Speed
(OSS) sensor while failure detection is not
achieved.
Cause of Failure
S Wiring harness or connector between Output Shaft
Speed (OSS) sensor and TCM
S OSS sensor
S TCM

5A2 – 218IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
TRANSAXLE DESCRIPTION
The new automatic transmission is an electronically con-
trolled 4–speed automatic transmission with Lock–up
mechanism.
The transmission is mainly composed of the torque con-
verter with lock up clutch, newly developed 4–speed plan-
etary gear unit, the hydraulic control system and the elec-
tric control system.
ELECTRONICAL COMPONENTS
Transmission Control Module (TCM)
The TCM primarily controls shift points and lockup en-
gagement. It is located on the driver side under the instru-
ment panel.
The transmission is controlled by an electronic shift sys-
tem. The Transmission Control Module (TCM) processes
input signals. From the information received, the TCM
controls the transmission hydraulic system.
The electronic shift system consists of the following :
S Transmission control module (TCM)
S Shift solenoids (SS1 and SS2)
S Pressure control solenoid (PCS)
S Lockup solenoid
S Input shaft speed (ISS) sensor
S Output shaft speed (OSS) sensor
S Transmission Fluid Temperature (TFT) sensor
S Transmission Range (TR) Switch
Transmission Range (TR) Switch
Transmission Range (TR) Switch transmits the informa-
tion which range includes shift lever of A/T to Starter and
TCM.
S It is possible for TR switch to start an engine in only
”P” and ”N”. (Prevention of reckless driving)
S TR switch makes backup lamp turn on when re-
versing.
S It is used for TR switch to shift control.
TR switch transmits the information by combination of
starter and reverse circuit to vehicle side directly without
TCM.
Shift Solenoid No 1,2 (SS1, SS2)
2 shift solenoids are installed directly in the valve body.
The solenoids operate of ON and OFF by the control sig-
nal from TCM. Combinations of 2 solenoids, SS1 and SS2
changes gear ranges.

POWER STEERING GEAR 6C – 7
DAEWOO V–121 BL4
SPEED SENSITIVE POWER STEERING SYSTEM
OPERATING WITH FULL ASSIST AT ALL TIMES
StepActionValue(s)YesNo
1Perform an initial inspection of the power steering
system.
Is the system operational?–Go to Step 2Go to
Section 6A,
Power Steering
System
2Check the speedometer.
Is the speedometer inoperative?–Go to
Section5,
TransaxleGo to Step 3
3Check the diagnostic trouble codes at the engine
control module (ECM).
Is the ECM code 24 set?–Go to
Section1F,
Engine
ControlsGo to Step 4
41. Turn the ignition ON.
2. Disconnect the electronic variable orifice (EVO)
solenoid actuator electrical connector at the
power steering pump.
3. Probe terminal 1 of the EVO actuator connec-
tor with a voltmeter.
Does the voltmeter display the specified value?–Go to Step 6Go to Step 5
5Repair the open or short in the circuit between termi-
nal 1 of the EVO solenoid actuator electrical connec-
tor and terminal 2 on the speed sensitive power
steering (SSPS) control module connector.
Is the repair complete?–System OK–
61. Remove the EVO solenoid actuator from the
power steering pump.
2. Turn the actuator upside down to position the
pintle.
3. Stimulate the actuator by connecting it to the
battery.
Does the actuator click?–Go to Step 8Go to Step 7
7Replace the EVO solenoid actuator.
Is the repair complete?–System OK–
81. Turn the ignition OFF.
2. Remove the SSPS control module from the
control module bracket.
3. Disconnect the SSPS control module connec-
tor.
4. Connect a test light from terminal 8 on the
SSPS control module connector to the ground.
5. Turn the ignition ON.
Is the test light on?–Go to Step 14Go to Step 9
9Check the ignition fuse.
Is the ignition fuse open?–Go to Step 10Go to Step 11
10Replace the ignition fuse.
Is the repair complete?–System OK–
11Check for an open or short in the circuit between ter-
minal 8 of the control module connector and the I/P
fuse block.
Is the connection faulty?–Go to Step 12Go to Step 13