The transmission fluid temperature (TFT) sensor is a positive temperature coefficient thermistor (temperature sensitive resistor) that provides information to the transmission control module (TCM) regarding transaxle fluid temperature. The temperature sensor is located in the valve body. Calculated temperature is a factor used to determine the shift time and the shift delay time.
The internal electrical resistance of the sensor varies in relation to the operating temperature of the transaxle fluid.
The TCM sends a 5-volt reference signal to the temperature sensor and measures the voltage rise in the electrical circuit. A higher fluid temperature creates a higher resistance in the temperature sensor, thereby measuring a higher voltage signal.
The TCM measures this voltage as another input to help control line pressure, shift schedules, and the torque converter clutch (TCC) apply. When the transaxle fluid temperature reaches 120°C (248°F), the TCM enters hot mode. Above this temperature, the TCM modifies the transaxle shift schedules and TCC apply in an attempt to reduce the fluid temperature by reducing transaxle heat generation.
• | The calculated temperature is compared with the predetermined minimum and maximum value. |
• | If the temperature is less than minimum value or greater than maximum value then the current temperature is regarded as of range and the corresponding error but will be set. |
• | Transmission fluid temperature is not between -40°C (-40°F) and 150°C (302°F). |
• | No lamp control required but diagnostic information should be stored immediately when malfunction is defected. |
• | TCM assumes the transaxle fluid temperature is 60°C (124°F). |
• | No influence on driveability. |
Using a scan tool can clear history DTCs.
When DTC P0710 sets, the possible cause of fault could be the transmission temperature sensor.
Step | Action | Values | Yes | No | ||||
---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||
2 |
Did either of the fail conditions occur? | -- | Go to Step 3 | Go to Diagnostic Aids | ||||
3 |
Is the resistance equal to the specified value? | TFT 25° C 990 ohms | Go to Step 7 | Go to Step 4 | ||||
4 |
Was a problem found? | -- | Go to Step 5 | Go to Step 6 | ||||
5 | Replace the automatic transaxle wiring harness. Is the replacement complete? | -- | System OK | -- | ||||
6 | Replace the TFT sensor. Is the action complete? | -- | System OK | -- | ||||
7 |
Is the resistance approximately equal to the specified value? | 0 ohms | Go to Step 9 | Go to Step 8 | ||||
8 |
Is the repair complete? | -- | System OK | -- | ||||
9 |
Is the voltage within the specified value? | 9-16 V | Go to Step 10 | Go to Step 11 | ||||
10 |
Is the repair complete? | -- | System OK | -- | ||||
11 | Replace the TCM. Refer to Transmission Control Module Replacement . Is the replacement complete? | -- | Go to Step 12 | -- | ||||
12 |
Has the last test failed or is the current DTC displayed? | -- | Go to Step 2 | System OK |