Page 1481 of 2643

5A1 – 132IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE(DTC) P1606
FAILURE OF EXTERNAL WATCHDOG
Circuit Description
The external watchdog will be triggered. If the external
watchdog does not run out after 30ms then the fault will be
detected.
Conditions for Setting The DTC
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
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 History DTCs can be cleared by using a scan tool.
Diagnostic Aids
S When DTC P1606 sets, the possible cause of fault
could be TCM.
Page 1482 of 2643

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 133
DAEWOO V–121 BL4
DTC P1606 – Failure Of External Watchdog
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 P1606?–Go to Step 3Go to ”Diag-
nostic Aids”
3Inspect EF1 or F2 fuse for open.
Was a problem found?–Go to Step 4Go to Step 5
4Replace the fuse as necessary.
Is the action completed?–System OK–
51. Turn the ignition OFF.
2. Disconnect the TCM wiring connector.
3. Inspect the wiring harness for short to battery
between the fuses (EF1 or F2) and the TCM
terminals (B3, C15, or C16).
Was a problem found?–Repair the wir-
ing harness.Go to Step 6
6Inspect the wiring harness for open between the
fuses (EF1 or F2) and the TCM terminals (B3, C15
or C16).
Was a problem found?–Repair the wir-
ing harness.Go to Step 7
7Inspect the wiring harness for open or short to
ground between TCM terminals (B12 or B13) and
G201.
Was a problem found?–Repair the wir-
ing harness.Go to Step 8
8Inspect the wiring harness for short to power be-
tween the terminals (B12 or B13) and G201.
Was a problem found?–Repair the wir-
ing harness.Go to Step 9
9Replace the TCM.
Is the replacement complete?–Go to Step 10–
101. 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 11Go to Step 2
111. Check if any DTCs are set.
2. Are any DTCs displayed that have not been
diagnosed?–Go to ”Applica-
ble DTC table”System OK
Page 1483 of 2643

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.
Page 1484 of 2643

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 135
DAEWOO V–121 BL4
DTC P1671 – CAN Transmit Message Failure
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. Turn the ignition OFF.
2. Disconnect the TCM wiring connector and
ECM wiring connector.
3. Measure the resistance between terminal A8 of
the TCM wiring connector and terminal K14 of
the ECM wiring connector.
4. Measure the resistance between terminal A16
of the TCM wiring connector and terminal K15
of the ECM wiring connector.
Is the resistance within the values shown?0ΩGo to Step 4Go to Step 3
3Repair the malfunctioning terminals as necessary.
Is the action complete?–System OK–
41. Turn the ignition ON.
2. Measure the voltage of terminal A8.
3. Measure the voltage of terminal A16.
Is the voltage within the values shown?11–14VGo to Step 5Go to Step 6
5Repair the short to power on the terminal(s) as nec-
essary.
Is the action complete?–System OK–
61. Replace the TCM.
2. Turn the ignition OFF and turn the ignition ON.
3. Check if P1671 DTC is set.
Is The DTC set?–Go to Step 7Go to Step 8
71. Replace the ECM.
2. Is the action complete?–Go to Step 8–
81. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Begin diagno-
sis againRepair verified
exit DTC chart
Page 1485 of 2643

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.
Page 1486 of 2643

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 137
DAEWOO V–121 BL4
DTC P1672 – CAN Bus Off Failure
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. Turn the ignition OFF.
2. Disconnect the TCM wiring connector and
ECM wiring connector.
3. Measure the resistance between terminal A8 of
the TCM wiring connector and terminal K14 of
the ECM wiring connector.
4. Measure the resistance between terminal A16
of the TCM wiring connector and terminal K15
of the ECM wiring connector.
Is the resistance within the values shown?0ΩGo to Step 4Go to Step 3
3Repair the malfunctioning terminals as necessary.
Is the action complete?–System OK–
41. Turn the ignition ON.
2. Measure the voltage of terminal A8.
3. Measure the voltage of terminal A16.
Is the voltage within the values shown?11–14VGo to Step 5Go to Step 6
5Repair the short to power on the terminal(s) as nec-
essary.
Is the action complete?–System OK–
61. Replace the TCM.
2. Turn the ignition OFF and turn the ignition ON.
3. Check if P1672 DTC is set.
Is The DTC set?–Go to Step 7Go to Step 8
71. Replace the ECM.
2. Is the action complete?–Go to Step 8–
81. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Begin diagno-
sis againRepair verified
exit DTC chart
Page 1487 of 2643

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.
Page 1488 of 2643

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 139
DAEWOO V–121 BL4
DTC P1673 – CAN Receive ECM Message Failure
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. Turn the ignition OFF.
2. Disconnect the TCM wiring connector and
ECM wiring connector.
3. Measure the resistance between terminal A8 of
the TCM wiring connector and terminal K14 of
the ECM wiring connector.
4. Measure the resistance between terminal A16
of the TCM wiring connector and terminal K15
of the ECM wiring connector.
Is the resistance within the values shown?0ΩGo to Step 4Go to Step 3
3Repair the malfunctioning terminals as necessary.
Is the action complete?–System OK–
41. Turn the ignition ON.
2. Measure the voltage of terminal A8.
3. Measure the voltage of terminal A16.
Is the voltage within the values shown?11–14VGo to Step 5Go to Step 6
5Repair the short to power on the terminal(s) as nec-
essary.
Is the action complete?–System OK–
61. Replace the TCM.
2. Turn the ignition OFF and turn the ignition ON.
3. Check if P1673 DTC is set.
Is The DTC set?–Go to Step 7Go to Step 8
71. Replace the ECM.
2. Is the action complete?–Go to Step 8–
81. After the repair, use a scan tool ”clear info”
function and road test the vehicle.
2. Review the ”DTC info”.
Has the last test failed or is the current DTC dis-
played?–Begin diagno-
sis againRepair verified
exit DTC chart