Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P0712: Transmission Fluid Temperature (TFT) Sensor Circuit Low VoltageDTC P0713: Transmission Fluid Temperature (TFT) Sensor Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Signal | P0712 | P0713 | P0713 | P0711 |
Typical Scan Tool Data
Display Parameters | Normal Range | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|---|
Trans. Fluid Temp. | -- | 160°C (320°F) | -40°C (-40°F) | -40°C (-40°F) |
Circuit/System Description
The transmission fluid temperature (TFT) sensor is a two wire sensor, consisting of a TFT sensor signal circuit and a low reference circuit, supplied by the transmission control module (TCM). The TFT sensor continuously monitors the temperature of the transmission fluid in the transmission sump. When the transmission fluid is cold the TFT sensor resistance is high, resulting in high voltage on the signal circuit. As the transmission fluid temperature increases, the TFT sensor resistance decreases, resulting in a lower voltage on the signal circuit. The TCM determines the transmission fluid temperature based on the voltage.
Conditions for Running the DTC
P0712
| • | DTCs P0711 and P0713 are not active. |
| • | Battery voltage is between 9-18 V. |
| • | Engine speed is greater than 200 RPM. |
P0713
| • | DTCs P0711 and P0712 are not active. |
| • | Battery voltage is between 9-18 V. |
| • | Engine speed is greater than 200 RPM. |
| • | Engine has been running for 20 seconds with a coolant temperature above 20°C (68°F). |
Conditions for Setting the DTC
P0712
This DTC sets when the TCM detects a transmission fluid temperature of 150°C (302°F) for 2.5 seconds.
P0713
This DTC sets when the TCM detects a transmission fluid temperature less than -45°C (-49°F) for 2.5 seconds.
Action Taken When the DTC Sets
P0712
| • | The TCM requests the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL) on the second occurrence. |
| • | The transmission fluid temperature defaults to engine coolant temperature or a calibration value. |
| • | DTC P0712 is stored in TCM history. |
P0713
| • | The TCM requests the ECM to illuminate the MIL on the second occurrence. |
| • | The transmission fluid temperature defaults to engine coolant temperature or a calibration value. |
| • | DTC P0713 is stored in TCM history. |
Conditions for Clearing the DTC
DTCs P0712 and P0713 are Type B DTCs.
Diagnostic Aids
| • | If both DTCs P0712 and P0218 are set in combination, diagnose P0712 prior to proceeding to P0218. |
| • | A short to ground on the reference circuit may allow P0712 to set. A fluid temperature of 160°C (320°F) observed on the scan tool may indicate that this has occurred. |
| • | You may have to drive the vehicle in order to experience a condition. |
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Inspect the transmission fluid level. Refer to Transmission Fluid Check.
- Perform a road test. Refer to Road Test.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed on the Freeze Frame/Failure Records data.
Circuit/System Testing
- Ignition OFF, disconnect the X175 harness connector at the transmission.
- Ignition ON, engine OFF, connect a 3A fused jumper wire to the TFT signal circuit terminal pin G, to TFT low reference circuit terminal H. Verify with a scan tool that the Trans. Fluid Temp. parameter changes from -40°C (-40°F) to 160°C (320°F) when the jumper is installed.
- Remove the transmission oil pan. Refer to Oil Pan Replacement.
- Test the transmission internal TFT signal and low reference circuits for a short to voltage, short to ground or and open/high resistance.
| ⇒ | If not the specified value, test the TFT reference voltage and ground circuits for a short to voltage, short to ground or an open/high resistance. If circuits test normal, replace the TCM. |
| ⇒ | If circuits test normal, test or replace the pressure switch manifold, with thermistor. |
Component Testing
Static Testing
- Ignition OFF, remove the pressure switch manifold from the valve body. Refer to Pressure Switch Manifold Replacement.
- Test for resistance between the signal circuit terminal E, and the low reference circuit terminal F. See transmission fluid temperature sensor table, refer to Temperature Versus Resistance.
Note: You must perform the Circuit/System Testing first.
| ⇒ | If not within the specified range, replace the pressure switch manifold, with thermistor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for TCM replacement, setup, and programming |
Repair Verification
If another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
