Circuit Description
The Automatic Transmission Fluid Temperature (TFT) sensor is a negative
coefficient thermistor. When the transmission fluid is cold, the sensor resistance
is high. As the transmission fluid warms, the sensor resistance decreases.
The TFT range is -40 to +150°C (-40 to +302°F).
The PCM provides a 5 volt reference through a fixed series resistor,
to the TFT circuit and monitors the voltage after the resistor, as the voltage
drop (signal) across the circuit.
If the PCM detects a large, rapid, fluid temperature change, or essentially,
no change from a cold start up, then DTC P0711 sets. DTC P0711
is a type D DTC.
Conditions for Setting the DTC
| • | No VSS DTCs P0502 or P0503. |
| • | System voltage is 10-16 volts. |
| • | No Transmission Component Slipping DTC P1870. |
| • | The TFT at start up is -40 to 21°C (-40 to 69°F). |
| • | The engine run time is 5 minutes or more. |
| • | The vehicle speed is 8 km/h (5 mph) or more for
7 minutes or more, cumulative this ignition cycle. |
| • | The TCC slip speed is 120 RPM or more for 7 minutes,
cumulative this ignition cycle. |
| • | The ECT is 70°C (158°F) or more. |
| • | The ECT has changed 50°C (90°F) or more since start up. |
| • | The TFT voltage is 0.20-4.92 volts. |
All of the above must be true and one of the following fail cases must
be true:
| | The change in TFT is 1.5°C (2.7°F) or less since start up for
7 minutes or more. |
| | The change in TFT is 20°C (36°F) or more within 0.2 seconds
for 14 times or more within 7 seconds. |
Action Taken When the DTC Sets
| • | The PCM does not illuminate the Malfunction Indicator Lamp (MIL). |
| • | The PCM calculates a transmission fluid default temperature as
follows: |
| • | If the Engine Run Time is less than 3 minutes and: |
| - | The Intake Air Temperature (IAT) DTC(s) P0112, P0113, P1111 or
P1112 is set, then the default Automatic Transmission Fluid Temperature (TFT)
is set to 0°C (32°F). |
| - | No IAT DTC is set, then the default TFT is set to the IAT value
which was saved at start up. |
| • | If the engine run time is greater than 3 minutes and: |
| - | The Engine Coolant Temperature (ECT) DTC(s) P0117, P0118, P1114
or P1115 is set, then the default TFT is set to 131°C (268°F). |
| - | No ECT DTC is set, and: |
| • | The ECT is less than 45°C (113°F), then the default TFT
is 12°C (54°F). |
| • | The ECT is greater than 115°C (239°F), then the default
TFT is 131°C (268°F). |
| - | No ECT DTC is set, the ECT is 45-115°C (113-239°F)
and: |
| • | The IAT DTC(s) P0112, P0113, P1111 or P1112 is set, then the default
TFT is set to equal the ECT. |
| • | The IAT at start up is less than 0°C (32°F), then the
default TFT is set to the ECT value minus 10°C (18°F). |
| • | The IAT at start up is greater than 28°C (82°F), then
the default TFT is set to the ECT value plus 10°C (18°F). |
| • | The IAT at start up is 0-28°C (32-82°F), then
the default TFT is set to equal the ECT value. |
Conditions for Clearing the DTC
| • | A scan tool can clear the DTC from the PCM history.
The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up
cycles without a failure reported. |
| • | The PCM cancels the DTC default actions when the fault no longer
exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
| • | Inspect the wiring at the PCM, the transmission connector and
all other circuit connecting points for the following conditions: |
| - | A broken wire inside the insulation |
| • | Test the TFT sensor at various temperature levels in order to
evaluate the possibility of a skewed (mis-scaled) sensor. |
| | Refer to Temperature vs Resistance
. |
| • | When diagnosing for an intermittent short or open condition, massage
the wiring harness while watching the test equipment for a change. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests for proper A/T fluid level and condition.
-
This step verifies
which condition has set DTC P0711.
-
The 12 volt test lamp is used as
a fixed resistance.
-
This step ensures that the PCM monitors circuit 1227.
P0711 Transmission Fluid Temperature Sensor Circuit -- Range/Performance
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Powertrain On-Board Diagnostic
(OBD) System Check performed?
| --
|
Go to Step
2
| Go to
Powertrain On Board Diagnostic (OBD) System Check
in Engine Controls
|
2
| Perform the Transmission Fluid Checking Procedure.
Refer to
Transmission Fluid Check
.
Did you perform the Transmission Fluid Checking Procedure?
| --
|
Go to Step 3
| Go to
Transmission Fluid Check
|
3
|
- Install the Scan Tool
.
- With the engine OFF, turn the ignition switch to the RUN position.
Important:: Before clearing the DTCs, use the Scan Tool
in order to record the Freeze Frame and Failure Records for
reference. Using the Clear Info function will erase the stored Freeze Frame
and Failure Records from the PCM.
- Record the DTC Freeze Frame and Failure Records, then clear the DTC.
- Select TFT Sensor voltage on the Scan Tool
.
- Drive the vehicle and observe the Scan Tool
for one of the following conditions:
| • | No TFT sensor voltage change. |
| • | Unrealistic, rapid, TFT sensor voltage fluctuations. The TFT change
is greater than 0.3 volts in any 2 second period. Note, on a
properly operating system as TFT increases from 50 to 60°C (122 to 140°F),
voltage will increase from about the 1 volt level to about the 3 volt
level then start to decrease again. Refer to Temperature vs Resistance
. |
Did either of the fail conditions occur?
| --
|
Go to Step 4
| Fault is not present. Refer to Diagnostic Aids
|
4
| Did the Scan Tool
display unrealistic
TFT voltage fluctuations?
| --
|
Go to Step
5
|
Go to Step 6
|
5
|
- Turn the ignition switch OFF.
- Disconnect the transmission 7-way connector. Additional DTCs may
set.
Using the J 35616-A
Connector Test Adapter Kit, install a 12 volt test lamp between terminals F and G
of the engine side of the transmission 7-way connector.
- Turn the ignition switch to the RUN position.
Does the Scan Tool
display an unrealistic TFT voltage fluctuation?
| --
|
Go to Step 7
|
Go to Step 8
|
6
|
- Record the Scan Tool
TFT display from step 3.
- Turn the ignition OFF.
- Disconnect the transmission 7-way connector. Additional DTCs may
set.
- Turn the ignition switch to the RUN position.
Is the Scan Tool
TFT the same as recorded from step 3?
| --
|
Go to Step
7
|
Go to Step 8
|
7
| Replace the PCM.
Refer to
Powertrain Control Module Replacement/Programming
in Engine Controls.
Is the replacement complete?
| --
|
Go to Step
9
| --
|
8
| Replace the TFT Sensor.
Refer to
Fluid Temperature Sensor Replacement
.
Is the replacement complete?
| --
|
Go to Step
9
| --
|
9
| In order to verify your repair, perform the following procedure:
| • | Operate the vehicle under the following conditions: |
| • | Drive the vehicle for at least 5 minutes from cool start. |
| • | The TFT changes by more than 3°C (5°F). |
| • | For a period of at least 7 seconds, the TFT sensor voltage
does not change more than 0.3 volts within 0.2 seconds. |
| • | Select Specific DTC. Enter DTC P0711. |
Has the test run and passed?
| --
| System OK
|
Go to Step
1
|
