Diagnostic Instructions
DTC Descriptor
DTC P0741 : Torque Converter Clutch (TCC) System - Stuck Off
DTC P0751: 1-2 Shift Solenoid (SS) Valve Performance - No First, Fourth or Fifth Gear
DTC P0756: 2-3 Shift Solenoid (SS) Valve Performance - No First or Second Gear
DTC P0761: 4-5 Shift Solenoid (SS) Valve Performance - No Fourth Gear
Circuit/System Description
The transmission control module (TCM) controls the torque converter clutch pulse width modulation (TCC PWM) solenoid valve. The solenoid controls the hydraulic fluid for TCC apply and release. When the TCC is fully applied, the engine is
coupled directly to the transmission through the TCC. The TCC used is an electronically controlled capacity clutch (ECCC). The TCM will normally allow a small amount of slip to occur with the ECCC. When the TCC is engaged, TCC slip speed is maintained
at approximately 20 to 50 RPM. The 1-2 shift solenoid (SS) valve, 2-3 SS valve and the 4-5 SS valve are supplied with fused ignition voltage. The ground path is controlled by the TCM. When the TCM commands the solenoid OFF, a ground
path is not provided and the filtered line pressure that is fed to the solenoid is exhausted. When the TCM commands the solenoid ON, a ground path is provided and the exhaust port is blocked, stopping the exhaust of line pressure. The TCM identifies a 1-2 SS
valve, 2-3 SS valve or a 4-5 SS valve condition by monitoring the commanded gear versus gear ratio. Refer to
Shift Solenoid Valve State and Gear Ratio
.
Conditions for Running the DTC
P0741
• | No TP sensor DTC P0120. |
• | No ISS DTCs P0716 or P0717. |
• | No OSS DTCs P0722 or P0723. |
• | No TCC stuck ON DTC P0742. |
• | No IMS DTCs P1820, P1822, P1823, P1825, P1826 or P1915. |
• | No engine torque signal circuit DTC P2637. |
• | No TCC solenoid electrical DTCs P2763 or P2764. |
• | The engine run time is greater than 5 seconds. |
• | The IMS range is D2, D3, D4, or D5. |
• | The elapsed time since the most recent range change is 6 seconds. |
• | The transmission fluid temperature is 20-130°C (68-266°F). |
• | The engine torque is greater than 55 N·m (41 lb ft). |
• | The throttle position is 10-90 percent. |
• | The gear ratio is within the following ranges: |
- | 1.56:1 to 1.64:1 - 3rd gear |
- | 0.98:1 to 1.03:1 - 4th gear |
- | 0.73:1 to 0.77:1 - 5th gear |
• | The TCC pressure is at least 200 kPa (29 psi) for 2 seconds or more. |
• | The TCC duty cycle is at least 80 percent for 2 seconds or more. |
P0751
• | No TP sensor DTC P0120. |
• | No ISS DTCs P0716 or P0717. |
• | No OSS DTCs P0722 or P0723. |
• | No TCC stuck ON DTC P0742. |
• | No shift solenoid electrical DTCs P0973, P0974, P0976, P0977, P0979, or P0980. |
• | No IMS DTCs P1820, P1822, P1823, P1825, P1826 or P1915. |
• | No engine torque delivered signal DTC P2637. |
• | The engine run time is greater than 5 seconds. |
• | The IMS range is not PARK, NEUTRAL or REVERSE. |
• | The transmission fluid temperature is 20-130°C (68-266°F). |
• | The throttle position is 10 percent or more. |
• | The input shaft speed is 200-6,800 RPM. |
• | The output shaft speed is 100 RPM or more. |
• | The engine torque is greater than 36 N·m (26.5 lb ft). |
P0756
• | No TP sensor DTC P0120. |
• | No ISS DTCs P0716 or P0717. |
• | No OSS DTCs P0722 or P0723. |
• | No TCC stuck ON DTC P0742. |
• | No shift solenoid electrical DTCs P0973, P0974, P0976, P0977, P0979, or P0980. |
• | No IMS DTCs P1820, P1822, P1823, P1825, P1826 or P1915. |
• | No engine torque delivered signal DTC P2637. |
• | The engine run time is greater than 5 seconds. |
• | The IMS range is not PARK, NEUTRAL or REVERSE. |
• | The transmission fluid temperature is 20-130°C (68-266°F). |
• | The throttle position is 10 percent or more. |
• | The input shaft speed is 200-6,800 RPM. |
• | The output shaft speed is 200 RPM or more. |
• | The engine torque is greater than 36 N·m (26.5 lb ft). |
P0761
• | No TP sensor DTC P0120. |
• | No ISS DTCs P0716 or P0717. |
• | No OSS DTCs P0722 or P0723. |
• | No TCC stuck ON DTC P0742. |
• | No shift solenoid electrical DTCs P0973, P0974, P0976, P0977, P0979, or P0980. |
• | No IMS DTCs P1820, P1822, P1823, P1825, P1826 or P1915. |
• | No engine torque delivered signal DTC P2637. |
• | The engine run time is greater than 5 seconds. |
• | The IMS range is not PARK, NEUTRAL or REVERSE. |
• | The transmission fluid temperature is 20-130°C (68-266°F). |
• | The throttle position is 10 percent or more. |
• | The input shaft speed is 200-6,800 RPM. |
• | The output shaft speed is 100 RPM or more. |
• | The engine torque is greater than 36 N·m (26.5 lb ft). |
Conditions for Setting the DTC
P0741
The TCM commands the TCC ON, and the TCC slip is between 150-250 RPM for greater than 8 seconds, 2 times during the same ignition.
P0751
Both of the following conditions must occur twice during the same trip:
• | The TCM commands 1st gear when the engine torque is greater than 40 N·m (30 lb ft) and the resulting gear ratio is 2.16:1-2.27:1 for 1.25 seconds. |
• | The TCM commands 4th or 5th gear when the engine torque is greater than 36 N·m (27 lb ft) and the resulting gear ratio is 1.56:1-1.64:1 for 5 seconds. |
P0756
Both of the following conditions must occur 3 times during the same trip:
• | The TCM commands 1st gear when the engine torque is greater than 40 N·m (30 lb ft) and the resulting gear ratio is 0.73:1-0.77:1 for 1.2 seconds. |
• | The TCM commands 2nd gear when the engine torque is greater than 36 N·m (27 lb ft) and the resulting gear ratio is 1.56:1-1.64:1 for 1.2 seconds. |
P0761
The TCM commands 4th gear and the resulting gear ratio is 0.73:1-0.77:1 for 4 seconds twice during the same trip.
Action Taken When the DTC Sets
P0741
• | DTC P0741 is a Type B DTC. |
• | The TCM inhibits 5th gear if the transmission is in Hot Mode. |
• | The TCM commands TCC OFF. |
• | The TCM freezes transmission adaptive functions. |
P0751
• | DTC P0751 is a Type B DTC. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | The TCM inhibits Autograde braking. |
• | The TCM inhibits TAP shift operation. |
P0756
• | DTC P0756 is a Type B DTC. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | The TCM commands HSD1 OFF. |
• | The TCM inhibits Powertrain braking. |
• | The TCM inhibits TAP shift operation. |
P0761
• | DTC P0761 is a Type B DTC. |
• | The TCM commands maximum line pressure. |
• | The TCM freezes transmission adaptive functions. |
• | The TCM inhibits Autograde braking. |
• | The TCM inhibits Powertrain braking. |
• | The TCM inhibits TAP shift operation. |
Conditions for Clearing the DTC
DTCs P0741, P0751, P0756 and P0761 are Type B DTCs.
Diagnostic Aids
If the DTC is cleared, then will not reset when the vehicle is driven, some of the following conditions may exist:
• | Restricted fluid circuits |
• | Inspect transmission fluid lines to radiator. Lines may be pinched, plugged or twisted. |
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Transmission General Description
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Transmission Control Module Scan Tool Information
Circuit/System Testing
- Perform the
Transmission Fluid Check
.
⇒ | Correct the transmission fluid level if the fluid is not at the proper level. |
- Using the scan tool, clear the DTC. If DTC P0741 was set, operate the vehicle in D5 at 72 km/h (45 mph) and use the scan tool to command the TCC ON. Observe the TCC Slip Speed parameter on the scan tool. The TCC Slip Speed should
be between -20 to 75 RPM.
⇒ | If the TCC Slip Speed is between 150-250 RPM for greater than 8 seconds, inspect the following components and repair or replace as necessary: |
- Using the scan tool, clear the DTC. If DTC P0751, P0756 or P0761 is set, drive the vehicle in D5 and ensure that the TCM commands 1st, 2nd, 3rd, and 4th gears. The ratios should match the commanded gear for all gears. Refer to
Shift Solenoid Valve State and Gear Ratio
.
⇒ | If the gear ratios do not match the commanded gear, inspect the following and repair or replace as necessary: |
P0751
• | The 1-2 shift valve O-ring worn or damaged. |
P0756
• | The 2-3 shift valve O-ring worn or damaged. |
P0761
• | The 4-5 shift valve O-ring worn or damaged. |
Component Testing
Disconnect the wiring harness connector from the affected solenoid. Measure the resistance for the affected solenoid. The resistance should be between 15-20.3 ohms for the 1-2 SS, 2-3 SS and the 4-5 SS. The resistance
should be between 10-13.6 ohms for the TCC PWM solenoid.
⇒ | If the resistance is not within the specified range, replace the affected solenoid. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the repair.
• | Allow the transmission to operate through all gears and all the TCC to engage. Ensure that the gear ratios match each commanded gear and the TCC slip speed is less than 75 RPM when the TCC is commanded ON. |