P0717

Circuit Description
The Automatic Transmission Input (shaft) Speed (A/T ISS) sensor provides Transmission Input Speed to the Vehicle Control Module (VCM). The A/T Input Speed Sensor (ISS) is a Permanent Magnet (PM) generator. The sensor mounts into the transmission case and maintains a slight air gap between the sensor and the forward clutch housing. The PM generator produces an AC voltage as the forward clutch housing rotor teeth pass through the sensor's magnetic field. The AC voltage level increases as the turbine shaft speed increases. The VCM converts the AC voltage into a digital signal. The VCM determines actual turbine speed using the digital signal. The VCM uses the input speed to calculate torque converter slip speed, and gear ratios.

When the VCM detects a low or no input speed during high vehicle and high engine speeds, then DTC P0717 sets. DTC P0717 is a type D DTC. For California emissions vehicles, DTC P0717 is a type B DTC.

Conditions for Running the DTC
^ No OSS DTC P0502 or P0503.
^ No TFP manual valve position switch DTC P1810.
^ TFP manual valve position switch is not PARK or NEUTRAL.
^ The vehicle speed is greater than 12 mph.
^ The engine runs greater than 475 RPM for at least 7 seconds, and not in fuel cutoff.

Conditions for Setting the DTC
The measured input speed is less than 25 RPM for at least 5.0 seconds.

Action Taken When the DTC Sets
^ For California emissions only, the VCM illuminates the Malfunction Indicator Lamp (MIL).
^ The VCM defaults the transmission to maximum line pressure.
^ The VCM freezes shift adapts.
^ The VCM stores DTC P0717 in VCM history.

Conditions for Clearing the MIL/DTC
^ For California emissions, the VCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
^ A scan tool clears the DTC from VCM history.
^ For California emissions, the VCM clears the DTC from VCM history if the vehicle completes 40 consecutive warm-up cycles without an emission related diagnostic fault occurring.
^ For Federal emissions, the VCM clears the DTC from VCM history if the vehicle completes 40 consecutive warm-up cycles without a non-emission related diagnostic fault occurring.
^ The VCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the VCM.

Diagnostic Aids
^ Inspect the wiring at the VCM, the OSS connector and all other circuit connecting points for the following:
- A backed out terminal
- A damaged terminal
- Reduced terminal tension
- A chafed wire
- A broken wire inside the insulation
- Moisture intrusion
- Corrosion
- The A/T ISS sensor harness being near the DIS components or the ignition wires.
^ When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
^ First diagnose and clear any engine DTCs or TP sensor codes that are present. Then inspect for any transmission DTCs that may have reset.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for proper circuit operation up to the VCM connections. Remove the fuel pump relay in order to eliminate a flooding condition during this step.
5. This step tests for proper operation of the ISS sensor.