Service Manual2005 Diagnostic Trouble Code (DTC) P0727

Nubira-Lacetti

Diagnostic Trouble Code (DTC) P0727

Engine Speed Input Circuit No Signal

Conditions for Setting the DTC

TCM detects that malfunction of engine speed signal for 2 seconds.
No DTCs U2105

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects a failure on the first ignition cycle.
No engine torque reduction control
No lock-up
No engagement pressure control
No 4th gear
No self-learning control
No timing solenoid control for N-D
TCM judges the engine revolution is 0 rpm.

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.

Cause of Failure

Wiring harness or connector between ECM and TCM
ECM
TCM

DTC P0727 Engine Speed Input Circuit No Signal

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform one vehicle drive cycle. Is the Malfunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector.
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0727 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector.
3	Turn the ignition OFF. Disconnect the TCM wiring connector and ECM wiring connector. Measure the resistance between terminal A17 of the TCM wiring connector and terminal 88 of the ECM wiring connector. Measure the resistance between terminal A7 of the TCM wiring connector and terminal 57 of the ECM wiring connector. Is the resistance within the values shown?	0 Ω	Go to Step 5	Go to Step 4
4	Repair the malfunctioning terminals as necessary. Is the action complete?	-	System OK	-
5	Turn the ignition ON. Measure the voltage of terminal A17. Measure the voltage of terminal A7. Is the voltage within the values shown?	11-14 v	Go to Step 6	Go to Step 7
6	Repair the malfunctioning terminals as necessary. Is the action complete?	-	System OK	-
7	Inspect the "Engine Speed". Refer to Section 1F, Diagnosis. Was a problem found?	-	Refer to Section 1F, Diagnosis.	Go to Step 8
8	Replace the TCM. Turn the ignition OFF. Turn the ignition ON. Check if P0727 DTC is set. Is the DTC set?	-	Go to Step 9	Go to Step 10
9	Replace the ECM. Is the action complete?	-	Go to Step 10	-
10	After the repair, use a scan tool "clear info" function and road test the vehicle. Review the "DTC info". Has the last test failed or is the current DTC displayed?	-	Begin diagnosis again	Repair verified exit DTC chart

Diagnostic Trouble Code (DTC) P0741

Torque Converter Clutch (TCC) Circuit Stuck Off

Conditions for Setting the DTC

Lockup solenoid is stuck OFF.
D range selected
Engine water normal temperature
20 seconds have passed since the transaxle was placed in D.
Engine revolution is 600 rpm or greater.
No failure of input speed sensor / engine revolution / water temperature signal / solenoid electrical / ranger sensor / throttle signal

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects failures on two consecutive ignition cycles.

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.

Cause of Failure

Lockup solenoid
Inside A/T
Inside valve body
TCM

DTC P0741 Torque Converter Clutch (TCC) Circuit Stuck Off

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform two vehicle drive cycles. Is the Maifunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector Inspection" in this section.)
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0741 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector Inspection" in this section.)
3	Turn the ignition OFF. Replace the master TCM and perform simulation test again under user condition. Is DTC P0741 reappeared?	-	Go to Step 4	Replace the TCM
4	Estimate the failure of lockup solenoid, lockup clutch or internal valve body. Inspect the lockup solenoid. Refer to "Unit Inspection" in this section. Is the condition of lockup solenoid OK?	-	Go to Step 5	Replace lockup solenoid
5	Estimate the failure of lockup clutch or internal valve body. Is problem found?	-	Replace the valve body assembly	System OK

Diagnostic Trouble Code (DTC) P0742

Torque Converter Clutch (TCC) Circuit Stuck On

Conditions for Setting the DTC

Lockup solenoid is stuck ON.
D range selected
Engine water normal temperature
20 seconds have passed since the transaxle was placed in D.
Engine revolution is 600 rpm or greater.
No failure of input speed sensor / engine revolution / water temperature signal / solenoid electrical / ranger sensor / throttle signal

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects failures on two consecutive ignition cycles.

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.

Cause of Failure

Lockup solenoid
Inside A/T
Inside valve body
TCM

DTC P0742 Torque Converter Clutch (TCC) Circuit Stuck On

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform two vehicle drive cycles. Is the Malfunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0742 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
3	Turn the ignition OFF. Replace the master TCM and perform simulation test again under user condition. Is DTC P0742 reappeared?	-	Go to Step 4	Replace the TCM
4	Estimate the failure of lockup solenoid, lockup clutch or internal valve body. Inspect the lockup solenoid. Refer to "Unit Inspection" in this section. Is the condition of lockup solenoid OK?	-	Go to Step 5	Replace lockup solenoid
5	Estimate the failure of lockup clutch or internal valve body. Is problem found?	-	Replace the valve body assembly	System OK

Diagnostic Trouble Code (DTC) P0743

Torque Converter Clutch (TCC) Electrical

Conditions for Setting the DTC

TCM detects that the ON signal of the lockup solenoid monitor during 0.5 seconds when lockup solenoid driver outputs the OFF signal.(When the TCC circuit is open or short to battery).
The above detection 2 times at shifting continuously.(When the Tcc circuit is open or short to battery).
TCM detects that the OFF signal of the lockup solenoid monitor during 0.3 seconds when lockup solenoid driver outputs the ON signal.(When the TCC circuit is short to ground).
The above detection 1 time at shifting continuously.(When the TCC circuit is short to ground).

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects failures on two consecutive ignition cycles.
No TCC lockup solenoid
1st gear fixed under the 10km/h

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.
TCM detects the ON signal of the lockup solenoid monitor during 160 ms when lockup solenoid driver outputs the ON signal and TCM detects the OFF signal of the lockup solenoid monitor during 160 ms when lockup solenoid driver outputs the OFF signal.

Cause of Failure

Wiring harness or connector between lockup solenoid and TCM
Lockup solenoid
TCM

DTC P0743 Torque Converter Clutch (TCC) Electrical

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform two vehicle drive cycles. Is the Malfunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector Inspection" in this section.)
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0743 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector Inspection" in this section.)
3	Turn the ignition OFF. Inspect the resistance between the vehicle harness and lock-up solenoid. Refer to "Unit Inspection" in this section. Disconnect the TCM connector (X-1) and inspect the resistance between the terminal A5 and A23. Is the measurement within the specified value?	20°C (68°F) 11-16 Ω	Go to Step 4	Go to Step 5
4	Estimate the failure of between the vehicle wiring harness connector and TCM. Inspect the connector. Refer to "Wiring Harness and Connector Inspection" in this section. Inspect the connection condition between the connectors (C-1). Is the connection condition OK?	-	Go to Step 6	Repair the wiring harness connectors.
5	Estimate the failure of between the vehicle harness and lockup solenoid. Disconnect the connector (X-3) of T/M wire and inspect the resistance between lock-up solenoid connector terminal 4 and ground. Is the measurement within the specified value?	20°C (68°F) 11-16 Ω	Go to Step 7	Go to Step 8
6	Replace the master TCM. Perform the reproducing test under user condition after confirming no DTC. Is DTC displayed?	-	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector Inspection" in this section.)	Replace the TCM
7	Estimate the failure of the vehicle wiring harness or between connectors. Inspect continuity and short circuit for the vehicle wiring harness and inspect the connection condition between connectors (C-3). Refer to "Wiring Harness and Connector Inspection" in this section. Is the condition OK?	-	Repair the temporary connection failure of connector	Replace the vehicle harness or adjustment between connectors
8	Estimate the failure of T/M wire or between connectors of lockup solenoid. Inspect the lockup solenoid. Refer to "Unit Inspection" in this section. Is the problem found?	-	Replace the lockup solenoid	Go to Step 9
9	Estimate the failure of T/M wire. Inspect continuity and short circuit for the T/M wire and inspect the connection condition between connectors (C-6). Refer to "Wiring Harness and Connector Inspection" in this section. Is the condition OK?	-	Repair the temporary connection failure of connector	Replace the T/M wire or adjustment between connectors

Diagnostic Trouble Code (DTC) P0748

Pressure Control Solenoid (PCS) Electrical

Conditions for Setting the DTC

TCM detects that the feed back voltage is greater than 4.9 volts and detects the detection 500 milliseconds continuously.(When the PCS circuit is short to battery).
TCM detects that the feed back voltage is less than 70.mV for 70 milliseconds and detects the 12.5 seconds continuously.(When the PCS circuit is short to ground or open).

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects a failure on the first ignition cycle.
No lockup control
No engine torque reduction control
No engagement pressure control
No 4th gear
No self-learning control
After failure decision : emergency mode

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.
TCM detects the feed back voltage is between 70mV and 4.9 v for 12.5 seconds continuously.

Cause of Failure

Wiring harness or connector between Pressure Control Solenoid (PCS) and TCM
PCS
TCM

DTC P0748 Pressure Control Solenoid (PCS) Electrical

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform one vehicle drive cycle. Is the Malfunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0748 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
3	Turn the ignition OFF. Inspect the resistance between the vehicle harness and Pressure Control Solenoid (PCS). Refer to "Unit Inspection" in this section. Disconnect the TCM connector (X-1) and inspect the resistance between the terminal A4 and A2. Is the measurement within the specified value?	20°C (68°F) 5.0-5.6 Ω	Go to Step 4	Go to Step 5
4	Estimate the failure of between the vehicle wiring harness connector and TCM. Inspect the connector. Refer to "Wiring Harness and Connector" in this section. Inspect the connection condition between the connectors (C-1). Is the connection condition OK?	-	Go to Step 6	Repair the wiring harness connectors.
5	Estimate the failure of between the vehicle harness and PCS. Disconnect the connector (X-3) of T/M wire and inspect the resistance between PCS connector terminal 3 and 8. Is the measurement within the specified value?	20°C (68°F) 5.0-5.6 Ω	Go to Step 7	Go to Step 8
6	Replace the master TCM. Perform the reproducing test under user condition after confirming no DTC. Is DTC displayed?	-	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)	Replace the TCM
7	Estimate the failure of the vehicle wiring harness or between connectors. Inspect continuity and short circuit for the vehicle wiring harness and inspect the connection condition between connectors (C-3). Refer to "Wiring Harness and Connector" in this section. Is the condition OK?	-	Repair the temporary connection failure of connector	Replace the vehicle harness or adjustment between connectors
8	Estimate the failure of T/M wire or between connectors of PCS. Inspect the PCS. Refer to "Unit Inspection" in this section. Is the problem found?	-	Replace the valve body assembly.(No replacement PCS by itself)	Go to Step 9
9	Estimate the failure of T/M wire. Inspect continuity and short circuit for the T/M wire and inspect the connection condition between connectors (C-6). Refer to "Wiring Harness and Connector" in this section. Is the condition OK?	-	Repair the temporary connection failure of connector	Replace the T/M wire or adjustment between connectors

Diagnostic Trouble Code (DTC) P0751

Shift Solenoid 1 (SS1) Stuck Off

Conditions for Setting the DTC

Shift Solenoid 1 (SS1) is stuck ON/OFF.
D range selected
Engine water normal temperature
20 seconds have passed since the transaxle was placed in D.
Engine revolution is 600 rpm or greater.
No failure of output speed sensor / input speed sensor / engine revolution / water temperature signal / solenoid electrical / ranger sensor / throttle signal

Action Taken When the DTC Sets

TCM will request the illumination of MIL and store DTC when TCM detects failures on two consecutive ignition cycles.

Conditions for Clearing the DTC

The TCM turns off the MIL when no further failures detected for three consecutive ignition cycles.
The scan tool can clear the DTC from the TCM history.
The TCM clears the DTC from the TCM history memory after forty consecutive warm up cycles without fault.

Cause of Failure

Shift Solenoid 1 (SS1)
Inside Valve Body
TCM

DTC P0751 Shift Solenoid 1 (SS1) Stuck Off

Step	Action	Value(s)	Yes	No
1	Turn the ignition OFF. Install the Scan tool. With the engine OFF, turn the ignition switch to the ON position. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu. Store Freeze Frame/Failure Records. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu. Clear DTC Information. Perform two vehicle drive cycles. Is the Malfunction Indicator Lamp (MIL) ON?	-	Go to Step 2	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
2	Select Request DTC by Status from the Diagnostic Trouble Codes Information menu. Request DTC by Status. Is DTC P0751 displayed?	-	Go to Step 3	Repair the temporary connection failure of connector (Refer to "Wiring Harness and Connector" in this section.)
3	Turn the ignition OFF. Replace the master TCM and perform simulation test again under user condition. Is DTC P0751 reappeared?	-	Go to Step 4	Replace the TCM.
4	Estimate the failure of Shift Solenoid 1 or internal valve body. Inspect the SS1. Refer to "Unit Inspection" in this section. Is the condition of SS1 OK?	-	Replace the valve body assembly.	Replace Shift Solenoid 1 (SS1).