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P0716



DTC P0716 or P0717

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 provide an overview of each diagnostic category.



DTC Descriptors
DTC P0716
- Input Speed Sensor (ISS) Performance

DTC P0717
- Input Speed Sensor (ISS) Circuit Low Voltage




Diagnostic Fault Information

* DTC P0716 detects a large change in the input speed signal in a very short period of time; an unrealistic change indicates an intermittent fault.
* DTC P0717 detects a very low input speed when the vehicle speed is greater than a calibrated value indicates a continuous fault.







Typical Scan Tool Data






Circuit/System Description

The automatic transmission ISS is a permanent magnet with a coil of wire wound around it. The ISS mounts in the case cover facing the reluctor wheel of the input shaft. As the reluctor wheel is driven by the turbine shaft, an AC signal is induced in the input speed sensor. Higher vehicle speeds induce a higher frequency and a higher voltage at the sensor. There is a fixed air gap between the sensor and the teeth on the sensor reluctor wheel. The ISS input is used by the transmission control module (TCM) in order to control line pressure, torque converter clutch (TCC) apply and release, and transmission shift patterns. This sensor is also used to calculate the appropriate gear ratios and TCC slippage.


Conditions for Running the DTC


P0716
* DTC P0717 has passed this ignition.
* No ISS DTC P0716 or P0717.
* No OSS/VSS DTC P0722 or P0723.
* No TP sensor DTC P0120 or P0220.
* No 1-2 shift solenoid valve DTC P0752, P0973, or P0974.
* Ignition voltage is between 8.0 and 18.0 volts.
* The engine speed is greater than 500 RPM for 5 seconds and not in fuel cut-off.
* The vehicle speed is 16 km/h (10 mph) or greater.
* The engine torque is greater than 50 N.m (37 lb ft).
* The ISS is greater than 1,050 RPM for at least 2 seconds.
* An increase in ISS is 500 RPM or less for at least 2 seconds.
* The calc. throttle position is 8 percent or greater.



P0717
* No ISS DTC P0717.
* No OSS/OSS DTC P0722 or P0723.
* Ignition voltage is between 8.0 and 18.0 volts.
* The engine speed is greater than 500 RPM for 5 seconds.
* The vehicle speed is 16 km/h (10 mph) or greater.
* The engine torque is greater than 50 N.m (37 lb ft).



Conditions for Setting the DTC

P0716

The input shaft speed changes by 1,000 RPM or greater for 3.25 seconds.

P0717

The input shaft speed is less than 50 RPM for 4.5 seconds.


Action Taken When the DTC Sets

* DTC P0716 and P0717 are type B DTCs.
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.
* The TCM calculates input speed based on engine speed and gear ratio.



Conditions for Clearing the DTC

DTC P0716 and P0717 are type B DTCs.


Diagnostic Aids

Inspect the ISS, wire harness, connector, and TCM for metallic debris, damage, or misalignment. Ensure the wiring harness is not stretched too tightly or other components are pressing on the automatic transmission inline 20-way connector body. Also inspect for proper clearance to any other components and wiring.


Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views
Description and Operation Reference

Transmission General Description (Transmission General 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
Special Tools

* J 44152 Jumper Harness (20 pins)
* J 44257 Main Wiring Harness Connector Remover



Circuit/System Verification

Start the engine in PARK and observe the transmission ISS on the scan tool while varying the engine speed. The transmission ISS should vary with the engine speed and not drop out.


Operate the vehicle within the Conditions for Running 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.


Circuit/System Testing

1. Start the engine and ensure the Transmission ISS parameter on the scan tool is greater than 100 RPM.

• If the value is less than 100 RPM, using the J 44257 main wiring harness connector remover, disconnect the automatic transmission inline 20-way connector and install the J 44152 jumper harness (20 pins) on the transmission pass-thru connector.

2. Measure the resistance between the ISS high signal circuit, pin S, and the ISS low signal circuit, pin V, of the J 44152 jumper harness (20 pins). The resistance should be between 820 and 1,428 ohms.

• If the value is greater than 1,428 ohms, test the ISS high signal circuit and the ISS low signal circuit for an open. If both legs of the circuit are good, replace the ISS.


• If the value is less than 820 ohms, test the ISS high signal and the ISS low signal circuits for a shorted together condition.

3. Measure the resistance of the ISS high signal circuit, pin S, to the transmission case. The resistance should be greater than 10K ohms.

• If the value is less than 10 ohms, replace the transmission wiring harness assembly.

4. Measure the resistance between the ISS high signal circuit, pin S, and all other circuits of the J 44152 jumper harness (20 pins), except the ISS low signal circuit, pin V. The resistance should be greater than 10K ohms.

• If the value is less than 10K ohms, replace the transmission wiring harness assembly.

5. Measure the resistance between the ISS low signal circuit, pin V, and all other circuits of the J 44152 jumper harness (20 pins), except the ISS high signal circuit, pin S. The resistance should be greater than 10K ohms.

• If the value is less than 10K ohms, replace the transmission wiring harness assembly.

6. Remove the J 44152 jumper harness (20 pins) from the transmission pass-thru connector and install it on the engine side of the harness. Measure the resistance between the ISS high signal circuit, pin S, and ground. The resistance should be greater than 10K ohms.

• If the resistance is less than 10K ohms, test the ISS high signal circuit for a short to ground.

7. Connect the negative probe of the DMM to a good ground. Ignition ON, engine OFF, probe the ISS high signal circuit, jumper harness pin S, and the ISS low signal circuit, jumper harness pin V, with the positive probe of the DMM. Measure the voltage for each circuit. The voltage should be between 2.4 and 2.6 volts.

• If the voltage is greater than 2.6 volts, inspect the affected circuit for a short to voltage.


• If the voltage is less than 2.4 volts, inspect the affected circuit for an open.

8. If all circuit/connections test normal, test or replace the TCM.



Component Testing

Verify that the ISS resistance is between 820 and 1,428 ohms.

If the resistance is not within the specified range, replace the ISS.



Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

* Input Speed Sensor Replacement (Service and Repair)
* Wiring Harness Replacement (Service and Repair)
* Control Module References for TCM replacement, setup, and programming


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