PRE-RELEASE
DTC P0741 or P0742
| DTC P0741 or P0742 |
| Diagnostic Instructions |
| • |
Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
|
|
| • |
Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
|
|
| • |
Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
|
|
| DTC Descriptors |
DTC P0741
Torque Converter Clutch (TCC) System Stuck Off
DTC P0742
Torque Converter Clutch (TCC) System Stuck On
| Diagnostic Fault Information |
| Component | Condition | DTCs | ||||||||||||
|
Valve Body Assembly
|
|
P0741, P0742
|
||||||||||||
|
Torque Converter
|
|
P0741, P0742
|
||||||||||||
| Circuit/System Description |
Based on input speed and output speed signals, signals from the engine control module (engine speed and throttle opening) and vehicle speed, smooth lock-up control and slip is performed through the lock-up control solenoid (SLU). The SLU is linearly turned ON and OFF. The lock-up clutch inside the torque converter is operated, and the pump impeller and turbine runner are connected. Through this, the engine and the automatic transmission are coupled and engine output is connected directly to the automatic transmission, eliminating transmission loss. Sliding the lock-up clutch when lock-up is in the OFF range, extends the lock-up range to low vehicle speeds. It also suppresses a rise in engine speed and increases transmission efficiency, improving fuel economy and at the same time, through the sliding of the lockup clutch, engine vibration can be absorbed by the torque converter.
| Conditions for Running the DTC |
P0741
| • |
The ignition voltage is 10.2-15.5 V.
|
|
| • |
The engine speed is greater less 4 000 RPM.
|
|
| • |
Engine torque is more than 0 Nm (0 lb ft).
|
|
| • |
The transmission is not in emergency mode.
|
|
| • |
Driving in D range.
|
|
| • |
TCM communication is normal.
|
|
| • |
DTCs P0716, P0717, P0721, P0722, P2759, P2762, P2763, P2764 are not set.
|
|
P0742
| • |
The ignition voltage is 10.2-15.5 V.
|
|
| • |
The engine speed is greater than 400 RPM.
|
|
| • |
Output speed is 0 RPM.
|
|
| • |
The transmission is not in emergency mode.
|
|
| • |
Driving in D range.
|
|
| • |
TCM communication is normal.
|
|
| • |
DTCs P0716, P0717, P0721, P0722, P2759, P2762, P2763, P2764 are not set.
|
|
| Conditions for Setting the DTC |
P0741
Detected slip speed is more than 100 RPM 2 s after lockup control is turned on.P0742
| • |
Detected slip speed is less than 100 RPM 2 s after lockup control is turned off.
|
|
| • |
Detects no slip speed in engine stall avoidance control after engine stall detected or no slip speed detected during no lockup control.
|
|
| Action Taken When the DTC Sets |
| • |
DTC P0741 is a Type B DTC.
|
|
| • |
DTC P0742 is a Type B DTC.
|
|
| • |
The TCM inhibits TCC.
|
|
| • |
The TCM freezes transmission adaptive functions.
|
|
| Conditions for Clearing the DTC |
P0741
| • |
DTC P0741 is a Type B DTC.
|
|
| • |
Deviation between Engine speed and output speed is less than 30 RPM during lockup control is turned on.
|
|
| • |
DTC P0742 is a Type B DTC.
|
|
| • |
Deviation between Engine speed and output speed is more than 100 RPM during lockup control is turned off.
|
|
| Diagnostic Aids |
Ensure the transmission fluid level, color and odor is correct and there are no leaks. If there are any other transmission DTCs set, diagnose those first.
| Reference Information |
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
| • |
Circuit Testing
|
|
| • |
Connector Repairs
|
|
| • |
Testing for Intermittent Conditions and Poor Connections
|
|
| • |
Wiring Repairs
|
|
Description and Operation
Transmission Component and System Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
| Circuit/System Verification |
Operate the vehicle in drive with the calculated throttle position greater than 8% and ensure TCC is commanded ON and OFF a minimum of 5 times.
| Circuit/System Testing |
Dynamic Test
| 1. |
Perform the line pressure check. Refer to
Line Pressure Check
.
|
|
| 2. |
Perform the transmission fluid check. Refer to
Transmission Fluid Level and Condition Check
.
|
|
| 3. |
If all circuits test normal, replace the K71 Transmission Control Module. Verify the DTC does not reset.
|
|
| 4. |
If the DTC resets, go to Component Testing.
|
|
| Component Testing |
Static Test
| 1. |
Inspect the valve body assembly for a stuck valve, debris, or damage.
|
|
| 2. |
If a stuck open or closed valve is found, replace the valve body assembly.
|
|
| 3. |
Inspect the torque converter assembly for damage or discoloration.
|
|
| 4. |
If you find a torque converter assembly concern, replace the torque converter assembly as necessary.
|
|
| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • |
Perform the torque converter diagnosis. Refer to
Torque Converter Diagnosis
.
|
|
| • |
Control valve body replacement-Refer to
Control Valve Body Replacement
for replacement, setup, and programming.
|
|
| • |
TCM-Refer to
Control Module References
for replacement, setup and programming.
|
|
| • |
Perform the
Transmission Adaptive Functions
.
|
|
