Test Description

WARNING: This page is about a different car, the 2004 Pontiac Grand Am and 2004 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

3: This step tests the ability of the PCM to detect an open circuit.
5: This step tests the TFT sensor for correct resistance.

DTC P0712 (3.4L)

Step	Action	Value(s)	Yes	No
1	Did you perform the Diagnostic System Check - Engine Controls?	-	Go to Step 2	Go to Diagnostic System Check - Engine Controls in Engine Controls - 3.4L
2	Install a scan tool. Turn ON the ignition, with the engine OFF. IMPORTANT: Before clearing the DTC, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the PCM. Record the DTC Failure Records. Clear the DTC. Select TFT Sensor on the scan tool. Does the scan tool display a TFT sensor voltage greater than the specified value?	0.33 V	Go to Intermittent Conditions in Engine Controls - 3.4L	Go to Step 3
3	Turn OFF the ignition. Disconnect the AT inline 20-way connector. Additional DTCs may set. Turn ON the ignition, with the engine OFF. Does the scan tool display a TFT sensor voltage greater than the specified value?	4.92 V	Go to Step 5	Go to Step 4
4	Test the signal circuit of the TFT sensor for a short to ground between the PCM connector C2 and the AT inline 20-way connector. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	-	Go to Step 11	Go to Step 10
5	Install the J 44152 jumper harness (20 pins) on the transmission side of the AT inline 20-way connector. Using the DMM and the J 35616 GM-approved terminal test kit, measure the resistance between the TFT sensor signal circuit and the low reference circuit of the J 44152 . Refer to Automatic Transmission Inline 20-Way Connector End View . Is the resistance within the range specified for the given transmission temperatures?	20° C (68° F) 3106-3923 ohm 100° C (212° F) 164-190 ohm	Go to Step 6	Go to Step 7
6	Measure the resistance between the TFT sensor signal circuit of the J 44152 and ground. Refer to Automatic Transmission Inline 20-Way Connector End View . Is the resistance less than the specified value?	1,000 ohm	Go to Step 9	Go to Intermittent Conditions in Engine Controls - 3.4L
7	Disconnect the TFP manual valve position switch from the automatic transmission wiring harness. Measure the resistance between the TFT sensor signal circuit and all other terminals of the J 44152 . Refer to Automatic Transmission Inline 20-Way Connector End View . Is the resistance less than the specified value?	1,000 ohm	Go to Step 9	Go to Step 8
8	Replace the TFP manual valve position switch. Refer to Transmission Fluid Pressure (TFP) Manual Valve Position Switch Replacement . Did you complete the replacement?	-	Go to Step 11	-
9	Replace the automatic transmission wiring harness. Refer to Wiring Harness Replacement . Did you complete the replacement?	-	Go to Step 11	-
10	Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement in Engine Controls - 3.4L. Did you complete the replacement?	-	Go to Step 11	-
11	Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Operate the vehicle under the following conditions: Turn ON the ignition, with the engine OFF. The TFT signal voltage must be greater than 0.33 volts for 10 seconds. Select Specific DTC. Enter DTC P0712. Has the test run and passed?	-	Go to Step 12	Go to Step 2
12	With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed?	-	Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 3.4L	System OK