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DTC P0720

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 P0720: Output Speed Sensor Circuit

Circuit/System Description

The output speed sensor (OSS) provides vehicle speed information to the transmission control module (TCM). This signal is used to control torque converter lock-up and gear change control.

Conditions for Running the DTC
    • Transmission is in Drive range.
    • Input speed is more than 1,000 RPM.
    • The voltage of the transmission fluid temperature sensor is between 0.1 and 2.4 V.
    • Throttle position is greater than 13 percent.

Conditions for Setting the DTC

Vehicle speed is less than 5 km/h (3 mph) for more than 2 seconds.

Action Taken When the DTC Sets
    • DTC P0720 is a Type A DTC.
    • Line pressure is maximum.
    • Lock-up control is inhibited.
    • The gear position is fixed as 3rd gear.
    • Torque down control is inhibited.

Conditions for Clearing the DTC

DTC P0720 is a Type A DTC.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Component Description

Electrical Information Reference

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

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON, observe the DTC information with a scan tool.
  2. Record Freeze Frame and Failure Records.
  3. Clear DTCs.
  4. Operate the vehicle under the conditions observed in the Failure Records.
  5. Observe the DTC information with the scan tool. Verify that DTC P0720 does not set.

Circuit/System Testing
  1. Ignition OFF, disconnect the B14A OSS wiring harness plug.
  2. Ignition ON with engine OFF, test for 11--14 V between the B14A OSS wiring harness plug terminal 1 and the terminal 3 (ground).
    3. ⇒If not the specified value, test for the circuit for open circuit or short circuit to ground.
  3. Test for the B14A OSS as Component Testing.
    4. ⇒If not the specified value, replace the B14A OSS.
  4. Test for continuity between the B14A OSS wiring harness plug terminal 2 and TCM wiring harness plug terminal 8 X2.
    5. ⇒If the continuity is not normal, repair or replace the circuit.
  5. If the circuits test normal, replace the K71 TCM.

Component Testing
  1. Move the select lever to the "N" range and release the parking brake.
  2. Raise the vehicle until the wheels leave the ground. Refer to Lifting and Jacking the Vehicle .
  3. Connect the resistor (1--10 kΩ between the B14A OSS harness connector terminal 1 and 2.

    4. Then connect the DMM.

  4. Turn the wheels (recommended to turn by hand).
  5. The DMM should output 0 V and 12 V alternately. If it does not, replace the B14A OSS.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Output Speed Sensor Replacement
    • Control Module References for TCM replacement, setup, and programming
   


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