OBD-II trouble code
P0717: Input / Turbine Speed Sensor No Signal
The input (turbine) speed sensor circuit is producing no signal at all while the transmission is clearly turning. Where P0715 covers an erratic or out-of-range reading, P0717 is the total-dropout case — the TCM sees nothing where it should see shaft speed.
Quick facts
- System
- Powertrain
- Category
- Transmission / Speed Sensor
- Severity
- High severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $150 – $800
- DIY difficulty
- Intermediate DIY
What does P0717 mean?
P0717 is the 'no signal' member of the input speed sensor family, and the contrast with P0715 is the key to diagnosing it. P0715 sets when the input/turbine speed signal is present but erratic, implausible, or out of range. P0717 sets when there is no signal at all — the TCM expects to see the input shaft turning (because the engine is running, a gear is engaged, and the vehicle is moving) but the input speed reads a flat zero. That clean dropout points hard toward an electrical open rather than a marginal sensor: a broken wire, a disconnected or corroded connector, a completely dead sensor, or in some cases a reluctor that's so damaged the sensor produces nothing.
The distinction matters because it changes where you look first. An erratic P0715-style signal makes you suspect a partially shorted wire, a chipped tone ring, or a sensor on its way out. A dead-flat P0717 signal makes you suspect a full open in the circuit — and the fastest test for that is to check the connector and wiring before anything else. A useful field check on many platforms: back-probe or unplug-and-inspect the sensor connector, and watch whether the signal reappears when you reseat it. Connectors that have corroded or backed out are a common, cheap cause of a complete signal loss.
Functionally, P0717 hits the transmission the same way P0715 does. The TCM relies on input speed to calculate gear ratio, verify the commanded gear, and manage converter slip and lockup. With the input signal gone entirely, it usually drops into limp mode — a single fixed gear with adaptive shifting disabled — to protect the hardware. The causes are the familiar three buckets weighted toward the electrical end: a failed sensor, an open or corroded wiring/connector path, and (less often) internal damage. Because the signal is fully absent rather than just noisy, wiring and connector inspection is the highest-yield first move on this code.
Common causes
- Open circuit in the input speed sensor wiring (broken or disconnected wire)
- Disconnected, backed-out, or heavily corroded sensor connector
- Completely failed input/turbine speed sensor
- Damaged reluctor / tone ring producing no readable pattern
- Chafed wire shorted to ground killing the signal
- Metal debris or fluid intrusion that has destroyed the sensor
- TCM internal fault on that sensor input (rare)
- Sensor left unplugged or mis-seated after a recent transmission repair
- Low or contaminated fluid contributing to sensor failure over time
Symptoms
- Check engine light on with P0717 stored
- Transmission locked in one gear (limp mode)
- Input speed reads zero in live data while the vehicle is clearly moving
- Harsh engagement and no adaptive shifting
- Torque converter clutch not locking up
- Possible speedometer or cruise-control effects on some platforms
- Symptom often appears suddenly and completely rather than intermittently
Diagnostic steps
- 1.Read live data with the vehicle moving and confirm the signature: input speed flat at zero while output speed and road speed are clearly non-zero indicates a complete signal loss.
- 2.Go straight to the connector and wiring. Because P0717 is a no-signal code, an open circuit or disconnected/corroded connector is the most likely cause — inspect and reseat first.
- 3.Unplug-and-inspect the sensor connector, looking for corrosion, backed-out pins, or fluid intrusion; reconnect and watch whether the signal returns.
- 4.Check continuity of the signal and ground wires from the sensor to the TCM to locate an open.
- 5.Resistance-check the sensor itself against spec — an open or out-of-spec reading confirms a dead sensor.
- 6.If the circuit and sensor test good, inspect the reluctor/tone ring for damage, which requires dropping the pan and is a larger job.
Repair cost
$150 – $800
Like P0715, the common case is an input speed sensor replacement at $150-$450, with labor depending on whether the sensor is external or behind the case. Because P0717 is specifically a no-signal code, wiring and connector repairs are an even more likely fix here — typically $100-$300 to repair an open or corroded connector. Transmission fluid service if needed: $150-$300. If the reluctor is damaged internally, expect $1,500-$3,000+ for the teardown. Inspect the wiring and connector before condemning the sensor — a backed-out connector is a frequent, cheap cause.
Estimate your repair
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Open the Repair Cost Estimator with transmission speed sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.