Engine-CodesScion – P0791 Scion

P0791 Scion Code - Intermediate Shaft Speed Sensor 'A' Circuit

Quick Answer

The P0791 diagnostic trouble code (DTC) for Scion vehicles relates to the Intermediate Shaft Speed Sensor 'A' Circuit. Common causes include Faulty intermediate shaft speed sensor, Damaged or corroded wiring/connectors, Issues with the transmission control module (TCM). Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0791 Scion indicates Intermediate Shaft Speed Sensor 'A' Circuit.
Common causes
Common causes include Faulty intermediate shaft speed sensor, Damaged or corroded wiring/connectors, Issues with the transmission control module (TCM).
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Table of contents Created and updated by William Orellana on Sep 11, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0791 Scion Description

The P0791 diagnostic trouble code (DTC) for Scion vehicles relates to the Intermediate Shaft Speed Sensor 'A' Circuit. This code indicates that there is a problem with the circuit that controls the intermediate shaft speed sensor. The intermediate shaft speed sensor is a crucial component of the vehicle's transmission system, as it helps to monitor the speed of the intermediate shaft which is responsible for transferring power from the engine to the transmission.

OBDII Code P0791 Scion - Intermediate Shaft Speed Sensor 'A' Circuit
P0791 Scion Code - Intermediate Shaft Speed Sensor 'A' Circuit

Common Causes of P0791 Scion

  1. Faulty intermediate shaft speed sensor
  2. Damaged or corroded wiring/connectors
  3. Issues with the transmission control module (TCM)
  4. Electrical interference or short circuits
  5. Mechanical issues within the transmission system

Symptoms of P0791 Scion

  1. Erratic or harsh shifting
  2. Transmission slipping
  3. Limp mode activation
  4. Check Engine Light illuminated
  5. Decreased fuel efficiency

How to Fix P0791 Scion

  1. Diagnose the issue by using a scan tool to retrieve the DTC and perform a visual inspection of the sensor and wiring.
  2. Replace the faulty intermediate shaft speed sensor if it is determined to be the cause of the problem.
  3. Check and repair any damaged or corroded wiring/connectors to ensure a proper connection.
  4. If the issue persists, inspect and test the TCM for faults and replace if necessary.
  5. Clear the DTC and test drive the vehicle to ensure the repair was successful.

Cost to Fix P0791 Scion

The typical repair costs for addressing the P0791 code can vary depending on the specific cause of the issue. In general, the cost of replacing the intermediate shaft speed sensor ranges from $100 to $300, including parts and labor. Additional costs may apply if wiring repairs or TCM replacement is needed. It's recommended to consult with a qualified mechanic or auto repair shop for a more accurate estimate based on the specific circumstances of your vehicle. Keep in mind that labor rates can vary, so it's advisable to compare prices from different service providers.

Need more information about the P0791 Scion code?

Need more information on how to fix the P0791 Scion code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0791 Scion code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0791 Scion Code

What does the OBDII code P0791 mean on a Scion?

P0791 indicates an issue with the Intermediate Shaft Speed Sensor 'A' Circuit, which monitors the rotational speed of the transmission's intermediate shaft for proper gear shifting.

What are common symptoms of the P0791 code on a Scion?

Common symptoms include erratic or delayed shifting, transmission slipping, poor fuel economy, and illumination of the check engine light.

What causes the P0791 code on a Scion?

Possible causes include a faulty intermediate shaft speed sensor, damaged wiring or connectors in the sensor circuit, or issues with the transmission control module (TCM).

Can a dirty or damaged speed sensor trigger the P0791 code?

Yes, dirt, debris, or physical damage to the intermediate shaft speed sensor can prevent it from functioning correctly and trigger the P0791 code.

How do I diagnose the P0791 code on a Scion?

Start by inspecting the wiring and connectors of the speed sensor for damage or corrosion. Use a scan tool to check live data and verify the sensor's readings and operation.

Can driving with the P0791 code damage my Scion's transmission?

Yes, ignoring this code can lead to improper transmission operation, which may cause increased wear or potential damage over time.

How can I fix the P0791 code on a Scion?

Repairs may involve replacing the intermediate shaft speed sensor, repairing or replacing damaged wiring, or reprogramming the transmission control module.

Is the P0791 code specific to Scion vehicles?

No, the P0791 code can appear on other vehicles with OBDII systems, but the exact diagnosis and repair steps may vary by make and model.

Does a faulty transmission control module cause the P0791 code?

Yes, a malfunctioning transmission control module can fail to process the speed sensor data correctly, which may result in this code.

What tools are needed to resolve the P0791 code on a Scion?

You’ll typically need an OBDII scanner, multimeter, and possibly basic hand tools to inspect wiring, test the sensor, and clear the code.

Discuss the causes and fixes for P0791 Scion OBDII Code

Code P0791 Scion comments

No comments found for this page.