Circuit Description
The Transmission Fluid Temperature (TFT) sensor contains a semiconductor device which changes resistance on the basis of the temperature (a thermistor). The TFT sensor is located inside the transmission in the main case wiring harness. The TFT sensor has a signal circuit and a ground circuit. The TCM applies a voltage (about 5.0 volts) on the signal circuit to the sensor. The TCM monitors the changes in this voltage that are caused by the changes in the resistance of the sensor in order to determine the transmission fluid temperature.
The TCM is able to measure a temperature range of -39°C to 208°C (-38°F to 406°F). The normal operating temperature of the transmission is approximately 80°C (176°F).
Conditions For Running The DTC
Tests continuously
Conditions for Setting the DTC
| • | The TFT is greater than 165°C (329°F). |
| • | The above condition met for longer than 16 seconds. |
Action Taken When the DTC Sets
| • | The MIL/STL will not illuminate. |
| • | The TCM memory stores the DTC at the time of the first failure. |
Conditions for Clearing the MIL/DTC
| • | A History DTC clears after forty consecutive warm-up cycles if no failures are present by this or any other non-emission related diagnostic. |
| • | The scan tool clears the MIL/DTC. |
Diagnostic Aids
This DTC is intended to indicate that an overheating condition has occurred. If the overtemperature event was of a short duration due to an unusual driving condition, there may be no fluid damage evident, or any other significant transmission damage. Investigate the following possible causes of a temporary transmission overtemperature condition:
| • | Towing uphill |
| • | Abusive operation of transmission |
| • | Extremely high ambient temperatures |
| • | Engine overheating |
For any test that requires probing the TCM harness connector or a component harness connector, use the Connector Test Adapter Kit J 35616 J 35616-A . Using this kit will prevent damage to the harness connector terminals.
Check for the following conditions:
| • | Poor connections at the TCM or at the component. Inspect harness connectors for any backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection. Refer to Engine Electrical, Troubleshooting Procedures, Checking Terminal Contact for proper procedure. |
| • | Damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the scan tool while moving any related connectors and any wiring harnesses. A change in the display may help to locate the fault. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||
2 | This DTC indicates an actual transmission overtemperature condition has occurred. Perform the transmission fluid checking procedure. On-Board Diagnostic System Check . Is there any evidence of the transmission overheating? | -- | Go to Automatic Transmission, Transmission On-Vehicle Service
| |
3 |
Do the indicated and the actual temperature readings agree within the range indicated? | ±3°C (± 5°F) | No trouble Found Refer to Diagnostic Aids | |
4 | Replace the TFT Sensor. Refer to Automatic Transmission, Transmission, On-Vehicle Service . Is repair complete? | -- | -- | |
5 |
Is DTC P0711 set? | -- | ||
6 | Were there any additional DTCs observed during the Powertrain or Transmission OBD System Check that have not been diagnosed? | -- | Go to the applicable DTC table | |
7 | Does the Transmission now function properly? | -- | System OK | Go to Functional Test |
