AutoCodes - OBDII Code List - P0742 BUICK

P0742 BUICK - Torque Converter Clutch Circuit Stuck On

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3
Table of contents

P0742 BUICK Possible Causes

  • Low transmission fluid level
  • Dirty transmission fluid
  • Faulty torque converter clutch solenoid valve
  • Torque converter clutch solenoid valve harness or connectors
  • Torque converter clutch solenoid valve circuit is open or shorted
  • Transmission internal mechanical problem

How do I fix code P0742 BUICK?

Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
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Tech Notes

When a transmission solenoid is stuck on, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is very dirty, it is recommended to change the transmission fluid and if possible removing the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a transmission mechanical failure and that the transmission will need to be rebuilt or replaced.

There is a factory service bulletin for the following Buick Models:
2001-2005 Buick LeSabre
2001-2005 Buick Park Avenue
2002-2007 Buick Rendezvous
2002-2007 Buick Rendezvous AWD
2005-2007 Buick Terraza
2005-2007 Buick Terraza EXT
2005-2007 Buick Terraza 4WD
2005-2008 Buick Allure (Canada Only)
2005-2008 Buick LaCrosse
2006-2008 Buick Lucerne
Buick Factory Service Bulletin OBDII Code P0742

Cost of diagnosing the P0742 BUICK code

Labor: 1.0

The cost of diagnosing the P0742 BUICK code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

When is the code detected?

When the Powertrain Control Module (PCM) no longer provides a ground path, the Torque Converter Clutch (TCC) solenoid valve de-energizes and apply fluid exhausts, releasing the TCC.
When the PCM detects low torque converter slip when the PCM commands the TCC OFF, then is sets the P0742 code.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P0742 BUICK Description

The Torque Converter Clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the Torque Converter Clutch Pulse Width Modulation (TCC PWM) solenoid valve in order to control fluid acting on the converter clutch apply valve. The TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. When grounded (energized) by the Powertrain Control Module (PCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circuit. The converter feed fluid applies the TCC.
OBDII Code P0742 Buick - Torque Converter Clutch Circuit Stuck On - AutoCodes.com

More Information

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Comments

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