GM Service Manual Online
For 1990-2009 cars only

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 Descriptor

DTC P0711: Transmission Fluid Temperature Sensor Performance

DTC P0712: Transmission Fluid Temperature Sensor Circuit Low Voltage

DTC P0713: Transmission Fluid Temperature Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Signal

P0712

P0711, P0713

P0711, P0713

P0711

Low Reference

-

P0711, P0713

P0711, P0713

P0711

Typical Scan Tool Data

Transmission Fluid Temperature

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: ignition switch ON, engine stop

Parameter Normal Range: -40°C to + 215°C (-40°F to +419°F)

Signal

-43°C (-45°F)

215°C (419°F)

215°C (419°F)

Low Reference

--

215°C (419°F)

215°C (419°F)

Circuit/System Description

The automatic transmission fluid temperature sensor provides transmission fluid temperature to the transmission control module (TCM). The TCM supplies a 5 V reference signal to the sensor. The automatic transmission fluid temperature sensor is a variable resistor that measures the temperature of the transmission fluid and is a thermistor, or a resistor that changes value when the temperature changes. The sensor has a negative temperature coefficient. This means that as the temperature increases the resistance decreases and vice versa. The TCM will compare the temperature difference between the engine coolant temperature sensor and the automatic transmission fluid temperature sensor to determine if the temperatures are within an acceptable operating range of each other. This fault is handled inside the TCM and no external circuits are involved.

Conditions for Running the DTC

P0711

    • The ignition voltage is between 10.2 V and 15.5 V.
    • The engine speed is greater than 400 RPM for 2 seconds.
    • TCM communication is normal.
    • DTCs P0712, P0713 are not set.
    • The transmission is not in emergency mode.
    • The engine speed is greater than 400 RPM for 10 minutes.
    • Vehicle speed was 40 km/h (25 MPH) or greater at once.

P0712

    • The ignition voltage is between 10.2 V and 15.5 V.
    • The engine speed is greater than 400 RPM for 2 seconds.
    • The transmission is not in emergency mode.
    • Driving in D range.
    • TCM communication is normal.

P0713

    • The ignition voltage is between 10.2 V and 15.5 V.
    • The engine speed is greater than 400 RPM for 2 seconds.
    • The transmission is not in emergency mode.
    • Driving in D range.
    • Driving time is more than 10 min.
    • TCM communication is normal.

Conditions for Setting the DTC

P0711

The automatic transmission fluid temperature is less than 20°C (36°F) after 10 minutes driving or more.

P0712

The automatic transmission fluid temperature is more than 200°C (473°F) for 10 s or more after consecutive 30 times.

P0713

The automatic transmission fluid temperature is lower than -43°C (-45°F) for 1 s or more after consecutive 12 times.

Action Taken When the DTC Sets

    • The TCM will default the transmission oil temperature to 80°C (353°F).
    • No lock-up slip control
    • No neutral control
    • No self learning control

Conditions for Clearing the DTC

DTCs P0711, P0712, and P0713 are Type C DTCs.

P0712, P0713

The automatic transmission fluid temperature is between 20°C and 150°C (68°F and 302°F) for 10 s or more.

Diagnostic Aids

A correct transmission fluid level is required for a proper function. The automatic transmission fluid temperature sensor is located inside the transmission at the valve body. To ensure that the shown oil temperature is correct, measure the oil temperature with an external thermometer.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Transmission Component and System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

LINK

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Perform the Transmission Fluid Check to verify correct fluid level.
  2. Engine idling at operating temperature, observe the scan tool Transmission Fluid Temperature parameter. The reading should be between -40°C and +215°C (-40°F and +488°F) and change.
  3. Operate the vehicle at about 60 km/h (37 MPH) for 10 minutes, verify the scan tool Transmission Fluid Temperature parameter varies by more than 2°C (3.5°F) to verify that the sensor is not stuck.

Circuit/System Testing

Operate the vehicle within the conditions for running and setting the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Component Testing

Static Test

  1. Ignition OFF, remove the K71 Transmission Control Module (TCM).
  2. Ignition OFF, test for infinite resistance between the low reference circuit terminal 7 (X2) and ground.
  3. If less than the specified range, replace the wiring harness.
  4. Ignition OFF, test for infinite resistance between the signal circuit terminal 8 (X2) and ground.
  5. If less than the specified range, replace the wiring harness.
  6. Test for infinite resistance between each terminal and the low reference circuit terminal 7 (X2) and also to the signal circuit terminal 8 (X2).
  7. If less than the specified range, replace the wiring harness.
  8. Test for the resistance between the B13 Automatic Transmission Fluid Temperature (TFT) Sensor signal circuit terminal 7 (X2) and the low reference circuit terminal 8 (X2). Refer to Transmission Fluid Temperature Sensor Specifications for the resistance values.
  9. If not within the specified range, replace the wiring harness.
  10. If the circuit test normal, replace the K71 Transmission Control Module (TCM).

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Wiring harness, refer to Automatic Transmission Wiring Harness Replacement for replacement
    • TCM, refer to Control Module References for replacement, setup and programming.
    • Perform the Transmission Adaptive Functions.