GM Service Manual Online
For 1990-2009 cars only

Object Number: 477446  Size: MF
Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The automatic transmission fluid temperature (TFT) sensor is a negative coefficient thermistor whose resistance value changes based on temperature. The PCM provides a 5 volt reference to the sensor. A low fluid temperature, an open TFT sensor or sensor circuit results in high signal voltage. The TFT operating range is -40°C to +151°C (-40°F to +304°F).

If the PCM detects a continuous open or a short to power on the TFT sensor circuit, then DTC P0713 sets. DTC P0713 is a type C DTC.

Conditions for Running the DTC

The system voltage is 9-18 volts.

Conditions for Setting the DTC

The PCM detects a TFT sensor voltage greater than 4.92 volts for 6 minutes and 40 seconds continuous.

Action Taken When the DTC Sets

    • The PCM does not turn on the malfunction indicator lamp (MIL).
    • The PCM freezes shift adapts.
    • The PCM calculates a default TFT from the ECT sensor and the IAT sensor.
    • The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records.
    • The PCM stores DTC P0713 in PCM history.

Conditions for Clearing the DTC

    • A scan tool can clear the DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 consecutive warm-up cycles without a non-emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids

    • Inspect the connectors at the controller, the component and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Wiring Systems.

Test Description

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

  1. A value above 4.9 volts indicates the fault is present. A value below 4.9 volts indicates the fault is intermittent.

  2. A value less than 0.2 volts indicates the PCM and engine wiring are good.

DTC P0713 TFT Sensor Circuit -- High Input

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain Diagnostic System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

2

Did you perform the transmission fluid checking procedure?

--

Go to Step 3

Go to Transmission Fluid Check

3

  1. Install a Scan Tool .
  2. Turn ON the ignition with the engine OFF.
  3. Important: Before clearing the DTCs, use the Scan Tool in order to record the Failure Records for reference. Using the Clear Info function will erase the stored Failure Records from the PCM.

  4. Record the Failure Records.
  5. Clear the DTCs.
  6. Using a Scan Tool , observe the TFT sensor voltage.

Does the Scan Tool display a TFT sensor voltage greater than the specified value?

4.9 volts

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn OFF the ignition.
  2. Disconnect the transmission 20-way connector.
  3. Connect the J 44152 jumper harness to the engine side of the 20-way connector.
  4. Connect a fused jumper wire from terminal L to terminal M of the J 44152 jumper harness.
  5. Refer to Automatic Transmission Inline Harness Connector End View .

  6. Turn ON the ignition with the engine OFF (additional DTCs may set).

Does the Scan Tool indicate that the TFT sensor voltage is less than the specified value?

0.2 volts

Go to Step 7

Go to Step 5

5

Test the signal circuit (CKT 1227) of the TFT sensor for an open between the PCM and the AT inline 20-way connector.

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 6

6

Test the ground circuit (CKT 2762) of the TFT sensor for an open between the PCM and the AT inline 20-way connector.

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

7

  1. Test the signal circuit (CKT 1227) of the TFT sensor for an open between the AT inline 20-way connector and the TFT sensor.
  2. Test the ground circuit (CKT 452) of the TFT sensor for an open between the AT inline 20-way connector and the TFT sensor.

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find the condition?

--

Go to Step 9

Go to Step 8

8

Replace the automatic transmission fluid temperature sensor.

Refer to Fluid Temperature Sensor Replacement .

Did you complete the replacement?

--

Go to Step 11

--

9

Replace the automatic transmission wiring harness assembly.

Refer to Solenoids and Wiring Harness Replacement .

Did you complete the replacement?

--

Go to Step 11

--

10

Replace the PCM.

Refer to Powertrain Control Module Replacement/Programming in Engine Controls.

Did you complete the replacement?

--

Go to Step 11

--

11

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Turn ON the ignition with the engine OFF.
  4. The TFT sensor voltage must be less than 4.9 volts for at least 6 minutes and 40 seconds.
  5. Select Specific DTC.
  6. Enter DTC P0713.

Has the test run and passed?

--

System OK

Go to Step 1