Fixing P0701 Error Code: Transmission Control System Malfunction

Having trouble with your car’s transmission? Don’t worry! In this article, we will delve into the P0701 error code, which indicates a transmission control system malfunction.

Understanding the causes and solutions for this error code can help you diagnose and resolve the issue. So, let’s get started!

Understanding the P0701 Error Code

When your vehicle’s onboard diagnostic system detects a malfunction in the transmission control system, it generates the P0701 error code. This code indicates that there is an issue with the transmission’s communication with the engine control module (ECM).

Causes of the P0701 Error Code

Several factors can contribute to the P0701 error code. Some common causes include:

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  1. Faulty Transmission Range Sensor: The transmission range sensor helps determine the position of the gear selector. A malfunctioning sensor can trigger the P0701 error code.
  2. Faulty Transmission Control Module: The transmission control module is responsible for managing the transmission’s functions. If it malfunctions, communication issues may arise, leading to the P0701 error code.
  3. Damaged Transmission Wiring: Faulty or damaged wiring can disrupt the communication between the transmission and the ECM, resulting in the error code.
  4. Low Battery Voltage: Insufficient voltage supply to the transmission control system can trigger the P0701 error code.

Diagnosing the P0701 Error Code

To fix the P0701 error code, follow these step-by-step instructions:

Step 1: Checking the Transmission Fluid

Start by checking the transmission fluid level and condition. Low or contaminated fluid can cause transmission-related issues, including the P0701 error code. Refer to your vehicle’s manual for the correct procedure to check the fluid level and add fluid if necessary.

Step 2: Inspecting the Transmission Wiring

Inspect the wiring harness connected to the transmission. Look for any signs of damage, frayed wires, or loose connections. If you notice any issues, repair or replace the damaged wiring as required.

Step 3: Testing the Transmission Range Sensor

Using a multimeter, test the transmission range sensor. Follow the manufacturer’s instructions to measure the sensor’s resistance or voltage values. If the readings are outside the specified range, consider replacing the sensor.

Step 4: Checking the Transmission Control Module

Inspect the transmission control module for any signs of damage or water intrusion. Clean the module’s connectors and ensure they are securely attached. If the module appears faulty, it may need to be replaced or reprogrammed.

Step 5: Verifying the Battery Voltage

Check the battery voltage using a voltmeter. Ensure the battery has a sufficient charge and that the voltage meets the manufacturer’s specifications. If the voltage is low, recharge or replace the battery.

Step 6: Conducting a Computer Diagnostic

Use an OBD-II scanner or take your vehicle to a trusted mechanic for a computer diagnostic. The scanner will retrieve error codes stored in the ECM and provide more detailed information about the specific problem causing the P0701 error code.

Step 7: Seeking Professional Help

If you have followed the previous steps and the error code persists, it is advisable to seek assistance from a qualified mechanic or transmission specialist. They have the expertise and equipment to diagnose and repair complex transmission issues effectively.

Tips for Preventing the P0701 Error Code

To minimize the chances of encountering the P0701 error code in the future, consider the following tips:

  • Regular Transmission Maintenance: Adhere to the manufacturer’s recommended maintenance schedule for your vehicle’s transmission. Regular fluid changes, filter replacements, and inspections can help prevent issues.
  • Avoid Harsh Driving: Excessive acceleration, abrupt gear changes, and aggressive driving can put stress on the transmission. Drive smoothly and avoid unnecessary strain on the transmission system.
  • Address Warning Signs Promptly: If you notice any unusual symptoms, such as slipping gears, delayed shifts, or strange noises, address them promptly. Ignoring such signs can lead to more severe transmission problems.
  • Use the Correct Transmission Fluid: Always use the recommended transmission fluid specified by the vehicle manufacturer. Using the wrong type of fluid can cause damage and lead to error codes like P0701.


The P0701 error code can be frustrating, but with the right knowledge and troubleshooting steps, you can resolve the issue. By following the outlined instructions and seeking professional help when needed, you can effectively diagnose and fix transmission control system malfunctions.


Can I continue driving with the P0701 error code?

  1. It is not recommended to ignore the P0701 error code and continue driving without addressing the underlying issue. Consult a professional to diagnose and fix the problem to ensure the proper functioning of your vehicle.

Can a faulty battery cause the P0701 error code?

  1. Yes, low battery voltage can contribute to the P0701 error code. Ensure your battery is in good condition and meets the manufacturer’s specifications to prevent voltage-related transmission issues.

Can I fix the P0701 error code myself?

  1. Some basic troubleshooting steps can be performed by DIY enthusiasts. However, due to the complexity of the transmission control system, it is advisable to seek professional help if the error code persists or if you lack experience in dealing with transmission-related repairs.