P0741

P0741-TORQUE CONVERTER CLUTCH CIRCUIT PERFORMANCE





For a complete wiring diagram Consult Diagrams/Electrical

Theory of Operation

The Transmission Control Module (TCM) constantly monitors the amount of torque converter slippage. When the torque converter clutch (TCC) is closed the slippage is expected to be below a predetermined threshold. If the slippage is more then expected when the TCC is closed, the DTC will set.

- When Monitored:
Ignition on, TCM not in initialization phase, No input speed sensor 1 or 2 (N2-N3) DTCs, No CAN bus or ECM DTCs, No CAN engine speed signal or engine torque signal not implausible DTCs, Engine speed greater than 450 rpm, No shift in progress, Gear 1, 2, 3, 4 or 5 engaged, and the TCM torque converter status is OPEN

- Set Condition:
The TCM detects TCC slippage greater than a calibrated value.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview

Diagnostic Test

1. CHECK FOR RELATED DTCS
Ignition on, engine off.
Using the scan tool, check DTCs.
Are there any Speed Sensor and/or TCC DTCs present?

Yes

- Diagnose and repair the DTC(s).

No

- Go to 2

2. TCC SOLENOID CONTROL CIRCUIT OPEN




Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Electrohydraulic Control Unit Assembly harness connector.
Measure the resistance of the TCC Solenoid Control circuit between the TCM and the Transmission Electrohydraulic Control Unit Assembly harness connector.
Is the resistance above 5.0 ohms?

Yes

- Repair the TCC Solenoid Control circuit for an open.
- Perform NAG1 TRANSMISSION VERIFICATION TEST.Verification Tests

No

- Go to 3

3. TCC SOLENOID CONTROL CIRCUIT SHORT TO GROUND




Measure the resistance between ground and the TCC Solenoid Control circuit.
Is the resistance below 5.0 ohms?

Yes

- Repair the TCC Solenoid Control circuit for a short to ground.
- Perform NAG1 TRANSMISSION VERIFICATION TEST.Verification Tests

No

- Go to 4

4. TCC SOLENOID CONTROL CIRCUIT SHORT TO ANOTHER CIRCUIT




Measure the resistance between the TCC Solenoid Control circuit and all other circuits in the Transmission Electrohydraulic Control Unit Assembly harness connector.
Is the resistance below 5.0 ohms between the TCC Solenoid Control circuit and all other circuits in the Transmission Electrohydraulic Control Unit Assembly harness connector?

Yes

- Repair the TCC Solenoid Control circuit for a short to another circuit(s).
- Perform NAG1 TRANSMISSION VERIFICATION TEST.Verification Tests

No

- Go to 5

5. TRANSMISSION CONTROL MODULE

NOTE: When the Transmission Control Module (TCM) detects and stores a DTC, the TCM also stores the vehicles operating conditions under which the DTC originally set. This information is located in the scan tool under Environmental Data. Before erasing any stored DTCs, record any available data to assist in duplicating the conditions in which the DTC originally set. Record the Environmental Data.

Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the TCM.
Road test the vehicle.
Does the DTC reset?

Yes

- Repair internal transmission. Pay particular attention to the components related to the TCC such as the Lockup Control valve, TCC solenoid, Valve Body, or the Torque Converter.
- Perform NAG1 TRANSMISSION VERIFICATION TEST.Verification Tests

No

- Test complete
- Perform NAG1 TRANSMISSION VERIFICATION TEST.Verification Tests