For 1990-2009 cars
Master Electrical Component List
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice

### Circuit Description

The automatic transmission fluid temperature (TFT) sensor is part of the 4L30-E automatic transmission internal wiring harness assembly. The TFT sensor is a thermistor, which is a resistor that changes value when the temperature changes. The sensor has a negative-temperature coefficient. This means that as the temperature increases, the resistance decreases, and as the temperature decreases, the resistance increases. The transmission control module (TCM) supplies a 5-volt reference signal to the sensor and measures the voltage drop in the circuit. When the transmission fluid is cold, the sensor resistance is high and the TCM detects high signal voltage. As the fluid temperature increases, the resistance decreases, which pulls down the signal voltage.

If the TCM detects an open in the TFT sensor or signal circuit, then DTC P0713 sets. DTC P0713 is a type C DTC.

### Condition for Running the DTC

The ignition is ON.

### Condition for Setting the DTC

TFT is above 4.35 Volts for 20 seconds.

### Action Taken When the DTC Sets

• | The TCM flashes the sport mode lamp.

• | The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM records this information as Failure Records.

• | The TCM stores DTC P0713 in TCM history.

• | The TCM uses a default temperature value of 130°C (266°F).

• | The TCM freezes shift adapts from being updated.

### Conditions for Clearing the STL/DTC

• | The TCM stops flashing the sport mode lamp as soon as the fault is no longer present.

• | A scan tool can clear the DTC.

• | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.

• | The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.

### Test Description

The numbers below refer to the step numbers on the Diagnostic Table.

1. This step tests for higher than normal circuit voltage which may also damage the TFT sensor.

2. This step simulates a TFT sensor DTC P0712. If the PCM recognizes the low signal voltage (high temperature), the PCM and the wiring are OK.

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

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission ? | -- | Go to Step 2 | Go to Powertrain On Board Diagnostic (OBD) System Check - Automatic Transmission
2 |

1. Install a Scan Tool .
2. Turn ON the ignition with the engine OFF.

Important: Record the Failure Records before clearing the DTCs. Using the Clear Info function erases the Failure Records from the ECM and the TCM.

3. Record the Failure Records.
4. Clear the DTC.

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

4.35 V

Go to Step 3

Go to Intermittent Conditions in Engine Controls

3 | Refer to Test Description for information about Step 3. Does the scan tool display a TFT voltage greater than the specified value? | 5.1 V | Go to Step 9 | Go to Step 4
4 |

1. Turn OFF the ignition.
2. Disconnect the transmission 7-way connector (multiple DTCs will set).
3. Install the J 44539 jumper harness on the TCM side of the 20-way connector.
4. Using the J 39200 digital multimeter (DMM) and the J 35616 connector test adapter kit, measure the voltage between jumper harness terminal F and a good ground.
5. Turn ON the ignition with the engine OFF.

Is the voltage within the specified value?

4.8-5.2 V

Go to Step 5

Go to Step 10

5 |

1. Turn OFF the ignition.
2. Install a fused jumper wire between terminals F and E of the transmission 7-way connector.
3. Turn ON the ignition with the engine OFF.

Is the Scan Tool TFT sensor signal voltage less than the specified value?

0.09 V

Go to Step 6

Go to Step 8

6 |

1. Turn OFF the ignition.
2. Install the J 44539 jumper harness to the transmission side of the 7-way connector.
3. Using the J 39200 DMM, measure the resistance between terminals F and E.

Is the resistance within the specified values?

Refer to Transmission Fluid Temperature Sensor Specifications

Go to Intermittent Conditions in Engine Controls

Go to Step 7

7 | Replace the AT main case wiring harness assembly. Refer to Control Valve Body . Is the action complete? | -- | Go to Step 12 | --
8 | Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

Inspect the Transmission Oil Temperature Sensor Low Reference (CKT XU716) for high resistance or an open.

Refer to Circuit Testing in Wiring Systems.

Did you find and correct a condition?

--

Go to Step 12

Go to Step 9

9 | Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

Inspect the Transmission Oil Temperature Sensor Signal circuit (CKT FP722) for a short to voltage B+.

Did you find and correct a condition?

--

Go to Step 12

Go to Step 10

10 | Caution: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs.

Inspect the Transmission Oil Temperature Sensor Signal circuit (CKT FP722) for high resistance or an open.

Did you find and correct a condition?

--

Go to Step 12

Go to Step 11

11 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the action complete? | -- | Go to Step 12 | --
12 | 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. Observe the Scan Tool TFT Sensor voltage.

Does the Scan Tool display a TFT Sensor voltage less than the specified value?

4.35

System OK

Go to Step 1