Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Buick Regal, 2002 Buick Century, 2001 Buick Regal, and 2001 Buick Century. 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.
Install a scan tool. Turn ignition on, engine off. Before clearing the DTCs, use the scan tool to record the failure records for reference. Using the CLEAR INFO function will erase the stored failure records from the PCM. Record the failure records. Clear the DTCs. With a scan tool, observe the TFT sensor parameter. Does the scan tool display a TFT sensor voltage greater than 4.9 volts? If so, go to next step. If not, see DIAGNOSTIC AIDS .
Turn ignition off. Disconnect the transaxle in-line 20-way connector. Connect the Jumper Harness (J 44152) to the engine side of the 20-way connector. Using the Connector Test Adapter Kit (J 35616-A), connect a DVOM from terminal "L" to terminal "M" of the jumper harness. Turn ignition on, engine off. Observe the voltage on the DVOM. Does the voltage measure within 4.9-5.0 volts? If so, go to step 7 . If not, go to next step.
Does the voltage in Step 3 measure more than 5.0 volts? If so, go to step 6 . If not, go to next step.
Test the signal circuit (CKT 1227) of the TFT sensor for an open between the PCM and the transaxle in-line 20-way connector. Test the low reference circuit (CKT 2762) of the TFT sensor for an open between the PCM and the transaxle in-line 20-way connector. Did you find and correct the condition? If so, go to step 14 . If not, go to step 13 .
Test the signal circuit (CKT 1227) of the TFT sensor for a short to power between the PCM and the transaxle in-line 20-way connector. Did you find and correct the condition? If so, go to step 11 . If not, go to step 13 .
Turn ignition off. Disconnect the transaxle in-line 20-way connector (additional DTCs may set). Install the jumper harness on the transaxle side of the transaxle in-line 20-way connector. Using the DVOM, measure the resistance between terminals "L" and "M" of the jumper harness. Is the resistance less than 100 k/ohms? If so, go to step 9 . If not, go to next step.
Test the signal circuit (CKT 1227) of the TFT sensor for an open between the transaxle in-line 20-way connector and the TFT sensor. Test the low reference circuit (CKT 452) of the TFT sensor for an open between the transaxle in-line 20-way connector and the TFT sensor. Did you find the condition? If so, go to step 10 . If not, go to step 12 .
Measure the resistance between terminal "L" and all other terminals, except "M", of the jumper harness. Is the resistance between terminal "L" and all other terminals, except "M", greater than 1000 ohms? If so, see DIAGNOSTIC AIDS . If not, go to next step.
Replace the transaxle internal wiring harness assembly. See TRANSAXLE INTERNAL WIRING HARNESS under REMOVAL & INSTALLATION. Did you complete the replacement? If so, go to next step.
Was the engine harness repaired, or the transaxle harness replaced due to a short to power or other circuit? If so, go to next step. If not, go to step 14 .
Replace the TFT sensor. See TRANSMISSION FLUID TEMPERATURE SENSOR under REMOVAL & INSTALLATION. Did you complete the replacement? If so, go to step 14 .
Replace the PCM. See POWERTRAIN CONTROL MODULE under REMOVAL & INSTALLATION. Did you complete the replacement? If so, go to next step.
Perform the following procedure to verify the repair:
- Select DTC.
- Select CLEAR INFO.
- Turn ignition on, engine off.
- The TFT sensor voltage must be less than 4.9 volts for at least 6 minutes and 40 seconds.
- Select SPECIFIC DTC.
- Enter DTC P0713.
Has the test run and passed? If so, system is okay. If not, go to step 1 .