P0742 Code: Meaning, Symptoms, Causes & Fix

Overview

Symptoms

• reduced acceleration
• harsh or delayed shifting
• transmission warning message

Common causes

• Failed internal motor/solenoid affecting torque converter clutch circuit stuck on
• Actuator stuck mechanically
• Connector pin damage/corrosion or harness stress near related components

How to diagnose P0742

1. Confirm P0742 and capture freeze-frame data with a professional scan tool.
2. Inspect wiring, connectors, and grounds related to torque converter clutch circuit stuck on for obvious defects.
3. Check actuator movement/mechanical travel and command response using scan tool bi-directional tests.
4. Check for related DTCs to identify the root-cause chain before replacing parts.
5. After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code P0742

Low: This code is low to moderate severity in most cases, but diagnosis is still recommended to avoid recurring warnings.

Can you drive with P0742?

The vehicle is often drivable with P0742, but plan a repair window to prevent repeat faults.

If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.

How to fix it (step-by-step)

1. Repair obvious wiring/connector faults first to prevent repeat parts replacement.
2. Address the root fault mode (stuck) in the torque converter clutch circuit stuck on circuit/system.
3. Apply the required relearn/adaptation procedure if specified by service information.
4. Road-test and verify P0742 remains cleared under the conditions that originally set the code.

Fix options

• Inspect mechanism for sticking or contamination.
• Replace stuck component and retest.
• Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$180-$650

Common mistakes when diagnosing P0742

• Replacing parts without verifying voltage, ground, and signal integrity first.
• Ignoring related stored/pending codes that indicate upstream faults.
• Skipping post-repair verification drive cycle and readiness checks.

P0742 in common vehicles

P0742 appears across makes such as BMW, Mercedes-Benz, Audi, Volvo. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes P0742?

P0742 is commonly set by stuck faults affecting torque converter clutch circuit stuck on.

How much does it cost to fix P0742?

For P0742, repair costs are typically $180-$650 depending on exact root cause, labor rates, and part quality.

Can I clear P0742 without repair?

You can clear P0742 temporarily, but the code usually returns until the underlying fault is corrected.

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