Operation CHARM: Car repair manuals for everyone.

P0741

Diagnostic Chart:




Wiring Diagram:






When torque converter clutch (TCC) is commanded On, the comparison of engine speed to turbine shaft speed is monitored to assure TCC is On. When TCC is On the engine speed and turbine shaft speed are equal. TCC is applied by grounding circuit 422.

DTC PARAMETERS

DTC P0741 is set when the PCM has detected the following conditions for more than 7.5 seconds twice per ignition cycle.

^ Transaxle fluid temperature above 20°C (68°F).

^ No engine or turbine shaft speed, or signal noise DTCs.

^ Engine speed is greater than 908 rpm.

^ Turbine shaft speed is greater than 224 rpm.

^ TCC has been commanded on for more than five seconds and there has been no gear change.

^ Speed difference across torque converter is greater than 280 rpm.

TEST DESCRIPTION

Numbered steps below refer to numbered steps on chart.

1. Check for DTCs P0781, P0756, P0758, P0761, P0763, P0782, P0766, P0768, P0783, P0740, P0743, P0744, P0759, P0764, or P0769. They must be eliminated first as a possible cause of DTC P0741.

2. Check actuator operation. Use actuator quick check. The actuator quick test will PWM the actuators at a set rate. Listen and compare the noise of TCC gear actuator to that of other actuators. The noise of all should be similar. Actuator Quick Chart

NOTE: To check actuator operation, command actuator quick test using the Scan tool.

3. Other possibilities for DTC P0741 to set:

^ Internal leakage in the TCC apply circuit.

^ Possible low line pressure.

^ Converter charge valve stuck causing TCC apply pressure to be exhausted to lube.

^ Converter limiting valve stuck open.

^ Missing or damaged torque converter-input shaft O-ring.

REPAIR VERIFICATION

Monitor DTC menu "Code Status" for "Pass Since Code Clear" and "Pass This Ignition Cycle." When both have passed, repair is verified.

Criteria for pass:

^ TCC commanded On

^ Ratio across torque converter is 1:1 for 12 seconds

DIAGNOSTIC AIDS

^ When the PCM detects a fault in the circuit (open, ground, short), the PCM will open the circuit internally to protect the circuit.

^ This DTC may be caused by a poor electrical connection at either the PCM, actuator connector plate, Instrument Panel Junction Block (IPJB) terminals, or Under Hood Junction Block (UHJB) terminals. Wiggling connectors while performing an actuator quick test may help isolate the problem area.

^ Due to the clutch priority valve, this DTC will be set when 2nd, 3rd or 4th gear is determined to be stuck on.

TCC Apply:

^ Engine temperature above 20°C (68°F).

^ Vehicle speed above 26 km/h (16 mph).

^ Transaxle fluid temperature above a given value in relation to intake air temperature sensor (IAT) value.

TCC Release:

^ Low engine speed down shift (i.e., light throttle, or steady) throttle with load increase.

^ Low end of 3rd gear speed range, brake on = TCC off.

^ Fast deceleration, i.e., brake lock on ice = TCC off gear = neutral.