Diagnostic Procedure
WARNING: This page does not describe the selected car, but rather 36 other vehicles, including the 2002 Pontiac Firebird, 2002 Oldsmobile Bravada, 2002 GMC Yukon XL, 2002 GMC Yukon, and 2002 GMC Sonoma. However, it is still accessible from the selected car via links, so may be relevant.
- Did you perform the diagnostic system check? If so, go to next step. If not, see DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM.
- Connect scan tool to DLC. Turn ignition on, engine off. Using scan tool, record freeze frame and failure records for reference. Test drive vehicle in "D4" range under steady acceleration, with a TP sensor angle greater than 20 percent. Monitor TCC slip speed on scan tool. If TCC slip speed is greater than 130 RPM when scan tool TCC ENABLE is YES, go to next step. If TCC slip is not greater than specified amount, see DIAGNOSTIC AIDS .
- TCC is hydraulically or mechanically stuck off. Check TCC PWM valve for a damaged exhaust orifice, converter apply valve being stuck off, misaligned or damaged valve body gasket, restricted apply valve passage or torque converter clutch for being mechanically stuck off. Repair as necessary. After repairs, go to next step.
- Test drive the vehicle in "D3" and hold the throttle at 20-99 percent and accelerate to 55 MPH. Ensure TCC is commanded on and the TCC slip speed is less than 50 RPM for 10 seconds. If DTC P0741 does not return, system is okay. If DTC P0741 returns, go to step 1.