The transaxle fluid temperature (TFT) sensor is a positive temperature coefficient thermistor, temperature sensitive resistor, that provides information to the transaxle 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 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, there by measuring a higher voltage signal.
The TCM measures this voltage as another input to help control line pressure, shift schedules and TCC apply. When transaxle fluid temperature reaches 120°C (248°F) the TCM enters hot mode. Above this temperature the TCM modifies transaxle shift schedules and TCC apply in an attempt to reduce 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 the minimum value or greater than the maximum value then the current temperature is regarded as of range and the corresponding error will be set. |
• | The hold lamp will blink. |
• | The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer. |
• | The TCM assumes the transaxle fluid temperature is 60°C (140°F). |
• | No influence on driveability |
• | The blinking hold lamp will turn OFF when the malfunction has not occurred after 3 ignition cycles. |
• | A history DTC will clear after 40 consecutive warm-up cycles without a fault. |
• | Using a scan tool can clear history DTCs. |
When DTC P0710 sets, the possible cause of the fault could be transaxle temperature sensor.
Step | Action | Value(s) | Yes | No | ||||
---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Automatic Transmission? | -- | 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? | 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 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 range? | 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 1 | System OK |