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, and then clear DTCs. Test drive vehicle in "D4" range and ensure PCM commands 1st, 2nd, 3rd and 4th gears. If a 1-1-4-4 shift pattern is detected, go to next step. If a 1-1-4-4 shift pattern is not detected, see DIAGNOSTIC AIDS .
- Check shift solenoids for damaged seals or internal malfunction. See appropriate AUTOMATIC article in TRANSMISSION SERVICING. Repair as necessary. After repairs, go to next step.
- Using scan tool, clear DTCs. Test drive vehicle in "D4" range. Hold throttle at 20 percent and accelerate vehicle to 55 MPH. If throttle moves more than 3 percent, stop vehicle and start again. Drive vehicle at 55 MPH for 2 miles. Check for DTCs. If DTC P0752 does not return, system is okay. If DTC P0752 returns, repeat step 1.