P0717: Input/Turbine Speed Sensor A No Signal (Meaning, Causes, Fixes)
What P0717 means
The input/turbine speed sensor reads how fast the transmission's input shaft is spinning. OBD-Codes.com describes it as a typically 3-wire electromagnetic sensor mounted in the transmission case near the rear of the bell housing, reading grooves or a notched reluctor wheel on the input shaft. The computer compares input speed with engine RPM, engine load and transmission output speed to control shifts. OBD-Codes.com says P0717 is set when the powertrain control module (PCM) detects no voltage output from the input speed sensor 'A' circuit, a complete loss of signal. RepairPal says the same: the input speed sensor isn't providing a signal, so the transmission control module (TCM) can't shift properly. It is a generic OBD-II code that applies to 1996 and newer vehicles, though repair steps vary by make and model. Related codes include P0715 (circuit), P0716 (range/performance) and P0718 (intermittent) for the same sensor.
Severity: can I keep driving?
Stop and fix promptly
Get it diagnosed soon and drive gently until you do. RepairPal rates P0717 Urgent, meaning it can cause severe damage or be unsafe, and says the transmission often drops into a default gear. Both sources list the transmission not shifting properly or at all, and OBD-Codes.com adds an erratic or dead speedometer. RepairPal also notes some cars stall when coming to a stop after highway driving. If the transmission is stuck in one gear, shifting harshly, or the car stalls, avoid highway driving and have it checked.
Common symptoms
- Check engine light on (RepairPal)
- Transmission won't shift properly, or won't shift at all (both sources)
- Erratic or harsh shift points (OBD-Codes.com)
- Intermittent, erratic or inoperative speedometer or odometer (OBD-Codes.com)
- Lower fuel economy (both sources)
- Stalling when coming to a stop after freeway driving, or misfire-like symptoms in some cases (RepairPal)
- Occasionally no noticeable symptoms (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Faulty input/turbine speed sensor (both sources)
- Damaged, loose or shorted wiring or connectors in the sensor circuit (both sources)
- Metal debris on the sensor's magnetic tip, or damaged grooves or reluctor notches (OBD-Codes.com diagnostic notes)
- PCM failure or a PCM programming error (OBD-Codes.com)
- Defective shift solenoids, valve body, or engine coolant temperature sensor (RepairPal)
- Dirty transmission fluid restricting hydraulic passages (RepairPal)
- The sources differ on causes: OBD-Codes.com limits them to the sensor, its wiring and the PCM, while RepairPal also lists shift solenoids, the valve body, the coolant temperature sensor and dirty fluid
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Read all stored codes and write down the freeze frame data. If there are also output speed sensor codes, OBD-Codes.com says to use live scanner data to see which circuit is actually failing.
- Check for technical service bulletins (TSBs) for your vehicle; there may be a known fix.
- Inspect the input speed sensor's wiring and connector for damage, corrosion or loose pins, and check the battery and cables.
- Check the transmission fluid level and condition; RepairPal lists dirty fluid as a possible cause.
- If you remove the sensor, be careful: OBD-Codes.com warns hot transmission fluid can escape and burn you. Clean any metal debris off the magnetic tip and check the reluctor wheel or grooves for damage before reinstalling.
Typical fixes
- Repair damaged wiring or connectors in the input speed sensor circuit
- Clean or replace the input/turbine speed sensor (RepairPal says to use OEM parts)
- Apply any available software update or reprogram the PCM/TCM
- Repair shift solenoids, the valve body or fluid problems if diagnosis points there (RepairPal)
- Replace the PCM only after all circuits and sensors test good (OBD-Codes.com)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- The transmission is stuck in one gear, slipping, or shifting harshly
- The car stalls when coming to a stop
- Testing needs the service manual's resistance and voltage specs, a digital multimeter and possibly an oscilloscope; OBD-Codes.com warns that testing without disconnecting related controllers can damage them
- The wiring and sensor check out and the code comes back, which points to deeper transmission or computer problems
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Is P0717 serious?
Yes, treat it as serious. RepairPal rates it Urgent, and both sources say the transmission may not shift properly or at all. The transmission often goes into a default gear, so drive gently and get it diagnosed soon.
What is the most common fix for P0717?
Both sources list a faulty input speed sensor and damaged wiring or connectors as causes. OBD-Codes.com recommends inspecting the wiring first and testing the sensor against the manufacturer's specs before replacing it; RepairPal says to check the connection, wiring and flexplate or flywheel teeth, then suspect the sensor.
Can P0717 affect my speedometer?
It can. OBD-Codes.com lists an erratic or inoperative speedometer and odometer among the symptoms.
How much does it cost to fix P0717?
Neither source gives a repair cost. The price depends on whether it's wiring, the sensor, or a deeper transmission problem, so get a diagnosis or a written estimate before replacing parts.
Sources
Last reviewed 2026-10-22. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.