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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Eldorado 🢒 Transmission/Transaxle 🢒 Automatic Transaxle - 4T80-E 🢒 DTC P0741 TCC System Stuck Off
Table 1: DTC P0741 TCC System Stuck Off

Object Number: 25443 Size: SF
Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice

Circuit Description

The PCM controls the torque converter clutch (TCC) solenoid valve pulse width modulation (PWM). The solenoid controls the hydraulic fluid for TCC apply and release. When the TCC is applied, the engine is coupled directly to the transmission through the TCC. The TCC slip speed should be near 0.

If the PCM detects high torque converter slip when the TCC is commanded ON, then DTC P0741 sets. DTC P0741 is a Type B DTC.

Conditions for Running the DTC
    • No MAF DTCs P0101, P0102, or P0103.
    • No TP DTCs P0121, P0122, or P0123.
    • No VSS DTCs P0502, or P0503.
    • No A/T ISS DTCs P0716, or P0717.
    • No TCC Stuck ON DTC P0742.
    • No TFP manual valve position switch DTC P1810.
    • No TCC PWM solenoid valve DTC P1860.
    • The engine run time is greater than 5 seconds.
    • The engine is not in fuel cut off.
    • The TFP manual valve position switch indicates D4.
    • The transmission gear ratio indicates 2nd, 3rd, or 4th gear.
    • The transmission fluid temperature is -18-130°C (0-266°F).
    • The throttle angle is greater than 8 degrees.
    • Delivered torque is between 43-202 N·m (32-150 lb ft).
    • The TCC solenoid valve is commanded ON at maximum duty cycle.

Conditions for Setting the DTC

TCC slip speed exceeds its limit for a given torque for 5 seconds.

Torque (lb ft)

Slip Speed Limit (RPM)

32

72

64

88

96

200

128

248

160

256

Action Taken When the DTC Sets
    • The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • SERVICE ENGINE SOON, SERVICE TRANSMISSION displays on the driver information center (DIC).
    • The PCM inhibits TCC engagement.
    • The PCM inhibits 4th gear if the transmission is in hot mode.
    • The PCM stores DTC P0741 in PCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.

Conditions for Clearing the MIL/DTC
    • The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
    • A scan tool clears the DTC from PCM history.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
    • Inspect the transmission fluid level.
    • The transmission may be in hot mode. Inspect the transmission fluid lines to the radiator. The lines may be pinched, plugged or twisted.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step inspects the transmission fluid to ensure that it is at the proper level.

    2.

  2. This step verifies that the TCC engages when commanded ON by the scan tool.

DTC P0741 TCC System Stuck Off

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Was the Transmission Fluid Checking Procedure performed?

--

Go to Step 3

Go to Transmission Fluid Check

3

  1. Install the Scan Tool .
  2. Turn the ignition switch to the RUN position.

    3. Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM.

  3. Record the Freeze Frame and Failure Records.
  4. Clear the DTCs.
  5. Drive the vehicle at 72 km/h (45 mph).
  6. Using the Scan Tool , command the TCC PWM solenoid valve ON.
  7. Monitor the TCC slip speed display

Is the slip speed within the specified parameters?

-5 to +80 RPM

Go to Diagnostic Aids

Go to Step 4

4
  1. Inspect for the following conditions:
    2. • The TCC control valve is stuck OFF due to sediment or binding.
    • The TCC regulator valve is stuck OFF due to sediment or binding.
    • The TCC feed valve is stuck OFF due to sediment or binding.
    • The oil pressure screen is clogged.
    • The TCC PWM solenoid valve O-ring is leaking or cut.
    • The turbine shaft seals are worn or cut.
    • The torque converter for ballooning
  2. Repair any of the above items as necessary.

Refer to Unit Repair.

Is the repair complete?

--

Go to Step 5

--

5

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Operate the vehicle under the following conditions:
    4. 3.1. Road test the vehicle with the gear select lever in D4.
    3.2. Ensure the TCC applies for more than 5 seconds.
  4. Select Specific DTC. Enter DTC P0741.

Has the test run and passed?

--

System OK

Go to Step 1