GM OBD2 Codes List P0717: Input Speed Sensor Circuit No Signal

The dreaded Check Engine Light can strike fear into the heart of any driver, especially when it’s accompanied by strange transmission behavior. If you’re a GM owner experiencing these symptoms and a code reader reveals the P0717 trouble code, you’re in the right place. This comprehensive guide will delve into the P0717 code, its causes, symptoms, and how to diagnose and fix it.

The P0717 code specifically refers to the “Input Speed Sensor Circuit No Signal.” This code is triggered when the Transmission Control Module (TCM), the brain behind your vehicle’s shifting, stops receiving a signal from the Input Speed Sensor. This sensor, often located on the side or top of the transmission case, is responsible for monitoring the rotational speed of the input shaft, which directly impacts gear selection and shift timing.

GM OBD2 Code P0717: Input Speed Sensor Location

Understanding the P0717 Code and its Implications

Without the Input Speed Sensor relaying accurate information, your GM’s transmission can experience a range of performance issues. This is because the TCM relies on this data to determine the appropriate gear for your vehicle’s speed and engine load.

Here’s a breakdown of the potential problems a P0717 code can indicate:

Faulty Input Speed Sensor: This is the most common culprit behind a P0717 code. Over time, the sensor can wear down, become contaminated with debris, or simply fail due to age and heat exposure.
Wiring Issues: The wiring harness connecting the sensor to the TCM can become frayed, corroded, or damaged, disrupting the signal flow.
Damaged Connector: The connector pins on the sensor or the TCM side can become bent, corroded, or loose, preventing a proper connection.
Transmission Range Sensor Malfunction: While less common, a faulty Transmission Range Sensor (also known as the neutral safety switch) can also trigger a P0717 code, as it provides information to the TCM about gear position.
TCM Failure: In rare cases, the TCM itself may malfunction, causing a loss of communication with the Input Speed Sensor.

Recognizing the Symptoms of a P0717 Code

While the Check Engine Light is a clear indicator, your vehicle might exhibit other symptoms that suggest a P0717 code and a faulty Input Speed Sensor:

Harsh or Erratic Shifting: The transmission may shift gears abruptly, jerk, or hesitate during acceleration or deceleration.
Slipping Transmission: The transmission may slip out of gear unexpectedly, causing a loss of power and a sudden surge in engine RPM.
Limp Mode: In severe cases, the TCM might put the transmission into “limp mode” as a safety precaution, limiting the vehicle’s speed and gear selection.
Inaccurate Speedometer Readings: Since the Input Speed Sensor also contributes to speedometer readings, a faulty sensor can cause inaccurate or fluctuating speeds.

Diagnosing and Fixing the P0717 Code

Before jumping into repairs, it’s crucial to diagnose the root cause of the P0717 code accurately.

Here’s a step-by-step approach to diagnose the P0717 code:

Read the Code: Use an OBD2 scanner to retrieve the trouble code and verify that it is indeed a P0717 code.
Inspect the Wiring and Connector: Visually inspect the wiring harness and connector for any signs of damage, corrosion, or loose connections. Repair or replace any faulty components as needed.
Test the Sensor: Use a multimeter to test the Input Speed Sensor’s resistance and voltage. Consult your vehicle’s repair manual for the specific resistance and voltage specifications. If the sensor fails the test, it needs to be replaced.
Check the Transmission Fluid: Low or dirty transmission fluid can affect sensor operation. Check the fluid level and condition. If it’s low, top it off. If it’s dirty or smells burnt, a transmission fluid flush and filter replacement might be necessary.
Consult a Professional: If the problem persists after checking the above components, it’s best to consult a qualified mechanic, especially if the TCM is suspected to be faulty.

GM OBD2 Code P0717: Diagnostic Tools

Addressing Frequently Asked Questions about P0717 Code

1. Can I still drive with a P0717 code?

While you might be able to drive short distances with a P0717 code, it’s not recommended. Driving with a faulty Input Speed Sensor can lead to further transmission damage and potentially leave you stranded.

2. How much does it cost to fix a P0717 code?

The cost of repair varies depending on the root cause. A simple sensor replacement might cost between $100 to $300, while more complex issues like wiring harness replacement or TCM repairs can cost significantly more.

3. How long does it take to replace an Input Speed Sensor?

Replacing an Input Speed Sensor is a relatively straightforward procedure for most mechanics and can typically be completed within an hour or two.

Need Further Assistance?

If you have more questions or need help diagnosing and fixing a P0717 code in your GM vehicle, don’t hesitate to reach out to our team of automotive experts. We’re available 24/7 to provide personalized support and guidance. Contact us via WhatsApp at +1(641)206-8880 or email us at [email protected].