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For 1990-2009 cars only

DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input 5.7L and 7.4L Gas


Object Number: 40806  Size: MF
Automatic Transmission Components 5.7L and 7.4L Gas
Automatic Transmission Controls Schematics 5.7L and 7.4L
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The Transmission Fluid Temperature (TFT) sensor is a thermistor that controls the signal voltage to the VCM. The VCM supplies a 5-volt reference signal to the sensor on circuit 1227. When the transmission is fluid is cold, the sensor resistance is high and the VCM senses a high signal voltage. As the transmission fluid temperature warms to normal operating temperature, the sensor resistance decreases and the voltage decreases to about 1.5-2 volts.

When the VCM detects a continuous open or short to the power in the TFT signal circuit or the TFT Sensor, then DTC P0713 sets. DTC P0713 is a type D DTC. For California emissions vehicles, DTC P0713 is a type B DTC.

Conditions for Setting the DTC

  1. The TFT Sensor indicates a voltage greater than 4.92 volts.
  2. The ignition is ON.
  3. All conditions met for 400 seconds.

Action Taken When the DTC Sets

    • The transmission default temperature is 140° C (275° F). The scan tool does not display the default temperature.
    • The VCM freezes shift adapts from being updated.
    • The VCM illuminates the Malfunction Indicator Lamp (MIL) for California Emission vehicles.

Conditions for Clearing the DTC

    • For California Emissions only, the VCM turns off the MIL after three consecutive ignition cycles without a failure reported.
    • A scan tool can clear the DTC from the VCM history. The VCM clears the DTC from the VCM history if the vehicle completes 40 warm-up cycles without a failure reported.
    • The VCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the VCM.

Diagnostic Aids

    • Inspect the harness for a faulty connection or an open in circuit 1227.
    • Inspect the wiring for poor electrical connections at the VCM. Inspect the wiring for poor electrical connections at the transmission 20-way connector. Look for the following conditions:
       - A bent terminal
       - A backed out terminal
       - A damaged terminal
       - Poor terminal tension
       - A chafed wire
       - A broken wire inside the insulation
    • When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change.
    • The scan tool displays the transmission fluid temperature in degrees. After the transmission operates, the temperature rises steadily to about 100° C (212° F). The temperature then stabilizes.
    • Test the TFT Sensor at the various temperatures in order to evaluate the possibility of a "skewed" (mis-scaled) sensor. Use the temperature to resistance value scale. A "skewed" sensor may cause firm shifts or TCC complaints.
    • First diagnose and clear any engine DTCs or TP Sensor codes that are present. Then inspect for any transmission DTCs that may have reset.

Test Description

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

  1. This step verifies a problem in the TFT sensor circuit.

  2. This step simulates a TFT Sensor DTC P0712. If the VCM recognizes the low signal voltage (high temperature), and the scan tool displays 146°C (295°F) or greater, the VCM and the wiring are OK.

  3. This step five inspects the TFT sensor and the internal wiring harness.

P0713

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Perform the transmission fluid checking procedure.

Refer to Transmission Fluid Check .

Did you perform the fluid checking procedure?

--

Go to Step 3

--

3

  1. Install the scan tool (tech 1) ®.
  2. With the engine OFF, turn the ignition switch to the RUN position.
  3. Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data.

  4. Record the DTC Freeze Frame and Failure Records.

Does the scan tool display a TFT Sensor signal voltage greater than the specified value?

4.92 volts

Go to Step 4

Go to Diagnostic Aids

4

  1. Turn the ignition OFF.
  2. Disconnect the transmission 20-way connector.
  3. Install J 39775 Jumper Harness on the engine side of the 20-way connector.
  4. Install a fused jumper wire from terminal L to terminal M on the engine harness.
  5. Turn the ignition to the RUN position.

Does the TFT Sensor signal a voltage drop to less than the specified value?

0.2 volts

Go to Step 5

Go to Step 9

5

  1. Turn the ignition OFF.
  2. Install the J 39775 Jumper Harness on the transmission side of the 20-way connector.
  3. Automatic Transmission Connector End View

  4. Using the J 39200 DVOM and the J 35616-A Connector Test Adapter Kit, measure the resistance between terminal L and terminal M.
  5. Refer to Electronic Component Description .

Is the resistance within specifications?

16,000ohms at -10°C (50°F) to 133ohms at 110°C (230°F)

Go to Diagnostic Aids

Go to Step 6

6

  1. Remove the transmission oil pan.
  2. Refer to Transmission Oil Pan Removal, in On-Vehicle Service.

  3. Inspect the internal wiring harness for an open.
  4. Refer to Electrical Diagnosis, Section 8.

Did you find a problem?

--

Go to Step 13

Go to Step 7

7

  1. Disconnect the internal wiring harness.
  2. Measure the resistance of the TFT Sensor.
  3. Refer to TFT Sensor Electronic Component Description .

Is the resistance within specifications?

16,000ohms at -10°C (50°F) to 133ohms at 110°C (230°F)

Go to Diagnostic Aids

Go to Step 8

8

Replace the internal wiring harness.

Refer to Automatic Transmission Internal Wiring Harness Assembly Replacement, in On-Vehicle Service.

Is the replacement complete?

--

Go to Step 13

--

9

Inspect circuit 1227 for an open or short to B+.

Refer to Electrical Diagnosis, Section 8.

--

Go to Step 13

Go to Step 10

10

Inspect circuit 470 for an open.

Refer to Electrical Diagnosis, Section 8.

Did you find a problem?

--

Go to Step 13

Go to Step 11

11

Inspect the VCM for faulty or intermittent connections.

Was a problem found?

--

Go to Step 13

Go to Step 12

12

Replace the VCM.

Refer to VCM Replacement/Programming , Section 6.

Is the replacement complete?

--

Go to Step 13

--

13

In order to verify your repair, perform the following procedure:

  1. Select DTC.
  2. Select Clear Info.
  3. Operate the vehicle so that the TFT Sensor indicates a voltage less than 4.92 volts for 400 seconds (6.7 minutes).
  4. Select Specific DTC P0713. Enter DTC .

Has the test run and passed?

--

System OK

Begin the diagnosis again. Go to Step 1.