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 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.

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

ISS High Signal

P0716, P0717

P0716, P0717

P0716, P0717

P0716, P0717

ISS Low Signal

--

P0716, P0717

--

P0716, P0717

Typical Scan Tool Data

Transmission Input Speed Sensor

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Operating Conditions: Engine running in PARK, normal operating temperature

Parameter Normal Range: 500-800 RPM

Transmission ISS

0 RPM

0 RPM

0 RPM

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

    • 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

    • 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.
    • 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

Connector End View Reference

    •  Component Connector End Views
    •  Inline Harness Connector End Views

Description and Operation Reference

    •  Transmission General Description
    •  Transmission Component and System Description
    •  Electronic Component Description
    •  Transmission Adaptive Functions
    •  Automatic Transmission Inline 20-Way Connector 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

Engine running. 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

    Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, using the remover J 44257 , disconnect the automatic transmission inline 20-way connector and install the jumper harness J 44152 on the transmission pass-thru connector.
  2. Using the light-blue test probes J 35616-65B from the most current J 35616 GM terminal test kit, test for 820-1428 Ω between the ISS high signal circuit jumper harness pin S and the ISS low signal circuit jumper harness pin V.
  3. If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, replace the ISS.
    If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the ISS.
  4. Test for greater than 10K Ω between the ISS high signal circuit jumper harness pin S and all other circuits of the jumper harness J 44152 , except the ISS low signal circuit jumper harness pin V.
  5. If less than the specified range, the affected circuits are shorted together. Replace the transmission internal wire harness.
  6. Test for greater than 250 Ω from the ISS high signal circuit jumper harness pin S and the ISS low signal circuit jumper harness pin V to the transmission case.
  7. If less than the specified value, test the affected circuits for a short to the transmission case. If both circuits test normal, replace the ISS.
  8. Using the remover J 44257 , remove the jumper harness J 44152 from the transmission pass-thru connector and install it on the engine side of the AT inline 20-way connector.
  9. Disconnect the X1 harness connector at the TCM.
  10. Important: When test probing TCM harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 GM terminal test kit. Use of the brown J 35616-6 (1.00 mm) PCM probe in a 0.64 mm terminal will deform the terminal, resulting in intermittent open conditions. The correct probe for TCM harnesses is the light blue J 35616-64B probe.

  11. Using the light blue probes J 35616-64B, test for greater than 250 Ω from the ISS high signal circuit jumper harness terminal S and the ISS low signal circuit jumper harness terminal V to a good ground.
  12. If less than the specified value, test the affected circuit for a short to ground.
  13. Using the light blue probes J 35616-64B , test for greater than 10K Ω between the ISS high signal circuit jumper harness terminal S and all other circuits of the jumper harness J 44152 .
  14. If less than the specified value, the affected circuits are shorted together.
  15. Using the light blue probes J 35616-64B , test for greater than 10K Ω between the ISS low signal circuit jumper harness terminal V and all other circuits of the jumper harness J 44152 .
  16. If less than the specified value, the affected circuits are shorted together.
  17. Using the light blue probes J 35616-64B, test the ISS high signal circuit for less than 10 Ω between the jumper harness J 44152 terminal S and terminal 3 X1 TCM.
  18. If greater than the specified value, repair the open or high resistance in the affected circuit.
  19. Using the light blue probes J 35616-64B, test the ISS low signal circuit for less than 10 Ω between the jumper harness J 44152 terminal V and terminal 26 X1 TCM.
  20. If greater than the specified value, repair the open or high resistance in the affected circuit.
  21. Using a 5A fused jumper wire and the light blue probes J 35616-64B, test for greater than 10K Ω between the ISS high signal circuit terminal 3 X1 TCM and all other circuits of X1 TCM.
  22. If less than the specified value, the affected circuits are shorted together.
  23. Using a 5A fused jumper wire and the light blue probes J 35616-64B, test for greater than 10K Ω between the ISS low signal circuit terminal 26 X1 TCM and all other circuits of X1 TCM.
  24. If less than the specified value, the affected circuits are shorted together.
  25. If all circuits and connections test normal, replace the TCM.

Component Testing

  1. Ignition OFF, using the remover J 44257 , disconnect the automatic transmission (AT) inline 20-way connector and install the jumper harness J 44152 on the transmission pass-thru connector.
  2. Using the light-blue test probe J 35616-65B from the most current J 35616 GM terminal test kit, test for 820-1428 Ω between the ISS high signal circuit jumper harness pin S and the ISS low signal circuit jumper harness pin V.
  3. If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, replace the ISS.
    If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the ISS.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Input Speed Sensor Replacement
    •  Wiring Harness Replacement
    •  Control Module References for TCM replacement, setup, and programming