P0741
DTC P0741 or P0742
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions 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
Circuit/System Description
The torque converter clutch (TCC) pressure control solenoid is part of the control solenoid valve assembly which has no serviceable parts. The TCC pressure control solenoid is a normally low pressure control solenoid. The TCC pressure control solenoid regulates transmission fluid to the TCC regulator valve in the lower valve body and the TCC control valve in the pump cover. When vehicle operating conditions are appropriate to apply the converter clutch, the Transmission Control Module will increase TCC pressure control current flow (duty cycle) to the TCC solenoid. The TCC pressure control solenoid directs fluid pressure to move the TCC control valve to the apply position, and moves the TCC regulator apply valve to the regulating position. The TCC regulator valve regulates TCC apply fluid pressure proportional to TCC solenoid pressure. When the TCC is fully applied, the engine is coupled directly to the transmission. TCC release is accomplished by the Transmission Control Module decreasing current flow to the TCC pressure control solenoid. This results in decreasing the apply pressure which allows the TCC control valve to move to the release position. The Transmission Control Module calculates torque converter slip speed based on engine speed and transmission input shaft speed.
Conditions for Running the DTC
P0741
* TCM DTC P0716, P0717, P0722, P0723, P0742, P2763, or P2764 is not set.
* ECM DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, or P042E is not set.
* Ignition voltage is between 8.6-32 V.
* The engine speed is between 400-7500 RPM for 5 seconds.
* The transmission fluid temperature (TFT) is -6.6 to +130°C (+20 to +266°F).
* The accelerator pedal position signal is valid.
* The throttle position is greater than 8 percent.
* The TCM must receive a valid torque signal from the ECM.
* The engine torque is greater than 50 Nm (36 lb ft).
* The TCC is commanded ON and PWM duty cycle is greater than 60 percent for 5 seconds.
* The following 6L80/6L90 gear ratios are achieved in the specified gear range while the TCC is commanded On:
- The 2nd gear ratio is between 2.19-2.52.
- The 3rd gear ratio is between 1.42-1.63.
- The 4th gear ratio is between 1.07-1.23.
- The 5th gear is between 0.79-0.91.
- The 6th gear is between 0.62-0.71.
* The following 6L50 gear ratios are achieved in the specified gear range while the TCC is commanded On:
- The 2nd gear ratio is between 2.20-2.53.
- The 3rd gear ratio is between 1.44-1.65.
- The 4th gear ratio is between 1.07-1.23.
- The 5th gear is between 0.79-0.91.
- The 6th gear is between 0.62-0.72.
P0742
* TCM DTC P0716, P0717, P0722, P0723, P0741, P2763, or P2764 is not set.
* ECM DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, or P042E is not set.
* DTC P0742 has not passed this key ON.
* Ignition voltage is between 8.6-32 V.
* The engine speed is 400-7500 RPM for 5 seconds.
* The transmission fluid temperature (TFT) is -6.6 to +130°C (+20 to +266°F).
* The accelerator pedal position signal is valid.
* The throttle position is greater than 8 percent.
* The TCM must receive a valid torque signal from the ECM.
* The engine torque is greater than 115 Nm (85 lb ft).
* The vehicle speed is greater than 16 km/h (10 mph).
* The gear ratio is between 0.62-1.63.
* The commanded gear is 2nd.
* The TCC is commanded OFF.
Conditions for Setting the DTC
P0741
* The TCC Pressure is greater than 750 Kpa (109 PSI) for 6 seconds.
* The TCM detects TCC slip greater than 130 RPM for 5 seconds when the TCC is commanded ON. This condition must occur 2 times.
P0742
The TCM detects the TCC slip between -50 and +13 RPM for 6 seconds when the TCC is commanded OFF. This condition must occur 2 times.
Action Taken When the DTC Sets
P0741
* DTC P0741 is a Type B DTC.
* The TCM inhibits TCC.
* The TCM inhibits high gear in hot mode.
* The TCM freezes transmission adaptive functions.
P0742
* DTC P0742 is a Type A DTC.
* The TCM disables neutral idle.
* The TCM enables high gear in hot mode.
* The TCM freezes transmission adaptive functions.
Conditions for Clearing the DIC/DTC
* DTC P0741 is a Type B DTC.
* DTC P0742 is a Type A DTC.
Diagnostic Aids
Before performing a road test, configure and setup the scan tool for snapshot mode. This will allow you to display, monitor, and verify multiple transmission data parameters at one time, after the road test.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics Electrical Diagrams
Connector End View Reference
* Component Connector End Views 5 Bow Lowered Switch (CM7)
* Inline Harness Connector End Views X102
Description and Operation
* Electronic Component Description Electronic Component Description
* Transmission Component and System Description Transmission Component and System Description
* Transmission General Description Transmission General Description
* Park - Engine Running Park - Engine Running
* Reverse Reverse
* Neutral - Engine Running Neutral - Engine Running
* Drive Range, First Gear Engine Braking First Gear Engine Braking
* Drive Range, First Gear First Gear
* Drive Range, Second Gear Second Gear
* Drive Range, Third Gear Third Gear
* Drive Range, Third Gear Default Third Gear Default
* Drive Range - Fourth Gear Fourth Gear
* Drive Range, Fifth Gear Fifth Gear
* Drive Range, Fifth Gear Default Fifth Gear Default
* Drive Range, Sixth Gear Sixth Gear
* Fluid Passages Fluid Passages
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
DT-47825 - Control Solenoid Test Plate
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
Note: If other DTCs are set, diagnose those DTCs first.
1. Engine idling in Park position, with parking brake applied and drive wheels chocked.
2. Verify the transmission fluid level and condition is correct. Refer to Transmission Fluid Level and Condition Check Transmission Fluid Level and Condition Check.
3. Ignition ON, clear the Transmission Control Module DTCs with a scan tool.
4. Verify the transmission operation performs as indicated in the road test instructions and DTCs P0741 or P0742 did not set. Refer to Road Test Initial Inspection and Diagnostic Overview.
• If DTC P0741 or P0742 set
Refer to Circuit/System Testing.
• If DTC P0741 or P0742 did not set
5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observe from the Freeze Frame/Failure Records data.
6. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing.
• If the DTC does not set
7. All OK.
Circuit/System Testing
1. Verify the transmission line pressures are within the specified ranges. Refer to Line Pressure Check Line Pressure Check.
• If the line pressures are not within the specified ranges
Refer to Fluid Pressure High or Low Fluid Pressure High or Low.
• If the line pressures are within the specified ranges
2. Ignition OFF. Remove the Q8 Control Solenoid Valve Assembly.
3. Verify a pressure change occurs for each solenoid when performing the solenoid test. Refer to Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test.
• If a pressure change does not occur for each solenoid
Replace the Q8 Control Solenoid Valve Assembly.
• If a pressure change does occur for each solenoid
4. Verify the conditions listed below do not exist. Carefully inspect each component for that condition. Repair or replace as necessary.
P0741 or P0742 - A/Trans Fluid Pump cover Assembly (219)
* TCC Control Valve (227) stuck/sticking - debris, binding, damaged valve, or scored bore.
* Converter Feed Limit Valve (220) stuck/sticking - debris, binding, damaged valve, or scored bore.
* Pressure Regulator Valve (233) stuck/sticking - debris, binding, damaged valve, or scored bore.
* Turbine Shaft Bushings (218), (228) damaged or loose.
* Leak between stator/tower assembly and cover.
P0741 - 4-5-6 (w/Turbine Shaft) Housing Assembly (441)
TCC Turbine Shaft O-ring Seal (443) damaged or leaking.
P0741 - Torque Converter Assembly (1)
* TCC friction material debonded or excessively worn.
* One way stator clutch distressed.
* Internal leak - missing or damaged seal.
* Overheated due to lack of lubrication/cooler flow.
P0741 or P0742 - Lower Control Valve Body Assembly (351)
* TCC Regulator Apply Valve (355) stuck/sticking - debris, binding, damaged valve, or scored bore. Bore plug (328) undersized or leaking.
* Clutch Select Valve 2 (352) stuck/sticking - debris, binding, damaged valve, or scored bore.
P0741 or P0742 - Q8 Control Solenoid Valve Assembly (314)
TCM incorrectly reporting high OSS, causing early TCC apply or late TCC release.
P0742 - A/Trans Input and Output Speed Sensor Assembly (303)
Incorrect, high, OSS signal, causing early TCC apply or late TCC release.
P0741 - Control Solenoid Valve Assembly (21)
A/Trans Fluid Pump Seal Assembly (18) damaged or leaking.
P0741 - Torque Converter Diagnosis
Refer to No Torque Converter Clutch Apply No Torque Converter Clutch Apply.
P0742 - Torque Converter Diagnosis
Refer to No Torque Converter Clutch Release No Torque Converter Clutch Release.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Perform the Reset Transmission Adapts Reset Procedure following all transmission related repairs.
* Refer to Control Module References Control Module References for control solenoid valve assembly replacement, programming, and setup.