P0717: How to Diagnose & Fix — Input/Turbine Speed Sensor Circuit No Signal
9 vehicles · 5 makes · $200-$4,500 repair
How to diagnose and fix P0717: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Mercedes-Benz E-Class · 2004–2012
The 722.9 7G-Tronic transmission conductor plate (internal electrical board with speed sensors) fails, causing limp mode, harsh shifting, and loss of gears. The electrical connector corrodes or the sensors crack from heat cycling.
Common Symptoms
- Transmission goes into limp mode (stuck in one gear)
- Harsh shifting between gears
How to Fix
Replace the conductor plate and both speed sensors inside the transmission. Requires dropping the transmission pan and valve body. Replace the transmission filter and fluid at the same time.
Owner tips & cautions
- TipThe conductor plate is a $150 part and 3-hour DIY job. Many shops quote $1,500+ because they don't differentiate it from a full valve body replacement.
Sources for this issue (4)
- ECU Testing: Mercedes 7G-Tronic TCM conductor plate failuremanufacturer
- MB Medic: 722.9 7G-Tronic Valve Body & Conductor Plate Must Readmedia
- UpFix: 722.9 Transmission Conductor Plate Repair Could Save $1000smanufacturer
- The Autopian: Heres What A Conductor Plate Is And Why It Kills So Many Mercedes Vehiclesmedia
Mercedes-Benz SLK/SLC · 2005–2011
The electronic conductor plate integrated into the 722.9 7-speed automatic's valve body (which houses the internal TCM, speed sensors and shift solenoids) is a widely reported failure on R171 SLKs equipped with the 7G-Tronic. As the plate's internal speed sensors and soldered joints degrade with heat cycling, the transmission drops into limp mode, typically locking into a single forward gear (often 2nd). The condition is temperature-sensitive and commonly appears from roughly 50,000-90,000 miles.
Common Symptoms
- Transmission stuck in gear (often 2nd), won't shift up
- Limp mode / reduced speed limited to ~40 mph
- Harsh or delayed shifts, especially when cold
- Intermittent faults that come and go with temperature
- Speed-sensor fault codes
How to Fix
Replace or rebuild the conductor plate (the revised design), refresh the valve body, and perform a transmission fluid and filter service plus an adaptation reset. Independent specialists offer a cheaper conductor-plate reman as an alternative to Mercedes' full valve-body replacement (roughly $2,000-$3,000 at a dealer). A neglected fluid service accelerates the failure, so periodic 722.9 fluid changes are recommended.
Sources for this issue (3)
Pontiac Bonneville · 1997–2005
The 4T65E (and 4T65E-HD behind the supercharged L67) used in 1997-2005 Bonnevilles develops progressively harder 1-2 and 2-3 shifts as the PCM adapts to lengthening shift times, eventually setting P1811 (Maximum Adapt and Long Shift). Owners on GM Forum and the Pontiac Bonneville Club describe a slam-shift that appears after 20-30 minutes of driving, then becomes constant. Root causes identified by the community and rebuilders are broken 1-2/2-3 accumulator springs, a worn pressure control solenoid (PCS), worn Teflon sealing rings, and burned 2nd/3rd clutch material clogging shift and EPC solenoids. Pre-2003 units also have a non-hardened 4th-clutch shaft that wears its teeth. GM TSB 02-07-30-022B covers harsh shifts with multiple transmission DTCs on 2000-2004 Bonnevilles, and TSB 04-07-30-028 covers fluid leaks from a reverse-servo seal that shrinks below 20F.
Common Symptoms
- Harsh or slamming 1-2 and 2-3 upshifts, worse once warm
- Check Engine light with P1811 stored
- Delayed or flared shifts before the hard-shift stage
- Shudder at light throttle 40-50 mph (TCC)
- Eventually slipping in 2nd, 3rd or reverse
How to Fix
Early stage: replace the pressure control solenoid (side-cover job) and the 1-2/2-3 accumulator springs/pistons (Transgo or TransTec accumulator kit T84167G is the community-standard fix), clear adaptives and refill with Dexron VI. Once slipping, overheated clutch smell, or P0730/P0717 codes appear the unit needs a rebuild with the hardened 4th-clutch shaft, updated bonded valve-body plate and new sealing rings, or a remanufactured unit (about $1,900 for the unit plus labor). No recall exists; TSB repairs were only free under warranty.
Sources for this issue (5)
- 1999 Pontiac Bonneville with hard shifting transmission - GM Forumforum
- T84167G Should resolve P1811 Code - GM Forumforum
- Transmission Experiences 4T65E - Especially Failure : Pontiac Bonneville Clubforum
- P1811 code on my 4T65E transmission, what are my options? - Bob Is The Oil Guyforum
- Pontiac Bonneville Transmission Problems and Cost (TSB 02-07-30-022B, 04-07-30-028)article
GMC Sierra 3500HD · 2008–2019
Pontiac Bonneville · 2004–2005
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P0717 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0717 mean?
P0717 stands for "Input/Turbine Speed Sensor Circuit No Signal." This transmission code means the computer is receiving no signal from the input/turbine speed sensor, which measures how fast the transmission's input shaft (turbine side of the torque converter) is spinning. The computer compares this against engine and output speeds to control shifts and torque converter lockup. With no signal, it can't manage shifting properly, so you may get harsh or erratic shifts, no torque converter lockup, or limp mode. It is a no-signal electrical fault pointing to the sensor or its circuit.
What are the most common causes of P0717?
The most common causes of P0717 are: Failed input/turbine speed sensor, Open or shorted wiring to the sensor, Corroded or loose sensor connector, Damaged reluctor/tone ring on the input shaft, Metal debris on the sensor tip from internal wear, Poor ground or reference voltage to the sensor, Faulty transmission control module (less common). The specific cause varies by vehicle.
How much does it cost to fix P0717?
Repair costs for P0717 range from $200 to $4,500, depending on the vehicle and root cause.
Which vehicles are affected by P0717?
Au7o has documented P0717 across 9 vehicle models from 5 manufacturers: Buick, Chevrolet, GMC, Mercedes-Benz, Pontiac.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.