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.
- Check transmission fluid level. Fill if necessary. See appropriate AUTOMATIC article in TRANSMISSION SERVICING. Go to next step.
- 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. Monitor TFT parameter while test driving vehicle. If TFT does not change more than 2.7°F (1.5°C) in 7 minutes since start-up, or TFT changes more than 36°F (20°C) in .2 second, 14 times within 7 seconds, go to next step. If neither of these conditions occurred, cause is intermittent. See DIAGNOSTIC AIDS .
- If scan tool displays a condition in which TFT does not change by more than 2.7°F (1.5°C) in 7 minutes since start-up, go to step 6. If scan tool does not display a condition in which TFT does not change by more than 2.7°F (1.5°C) in 7 minutes since start-up, go to next step.
- Turn ignition off. Disconnect transmission 20-pin in-line harness connector. Install appropriate jumper harness on engine side of in-line harness connector. Connect test light between terminals "L" and "M". Turn ignition on, engine off. While monitoring scan tool, wiggle engine wiring harness from appropriate PCM harness connector to transmission 20-pin in-line harness connector. If TFT temperature changes by more than 36°F (20°C), go to step 7. If TFT temperature does not change by more than 36°F (20°C), go to step 8.
- Turn ignition off. Disconnect transmission 20-pin in-line harness connector. Turn ignition on, engine off. If scan tool displays a condition in which TFT does not change by more than 2.7°F (1.5°C) in 7 minutes since start-up, go to step 11. If scan tool does not display a condition in which TFT does not change by more than 2.7°F (1.5°C) in 7 minutes since start-up, go to step 10.
- Check for intermittent open or short condition in TFT sensor signal circuit between PCM and transmission 20-pin in-line harness connector. Repair as necessary. After repairs, go to step 12. If circuit is okay, go to step 11.
- Check for intermittent open or short condition in TFT sensor signal circuit between transmission 20-pin in-line harness connector and TFT sensor. If circuit is faulty, go to next step. If circuit is okay, go to step 10.
- Replace transmission wire harness assembly. See appropriate AUTOMATIC article in TRANSMISSION SERVICING. After repairs, go to step 12.
- Replace TFT sensor. See appropriate AUTOMATIC article in TRANSMISSION SERVICING. After repairs, go to step 12.
- Replace PCM. After replacement, program PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After repairs, go to next step.
- Using scan tool, clear DTCs. Road test vehicle. Monitor transmission fluid temperature. Ensure rise in fluid temperature is greater than 4°F (2.25°C) within 11 seconds since start-up, and fluid temperature does not change by more than 36°F (20°C) within .2 second for a period of at least 11 seconds. Check for DTCs. If DTC P0711 does not return, system is okay. If DTC P0711 returns, repeat step 1.
NOTE:
TFT sensor is part of TFP manual valve position switch.