P0601 Code: Internal Control Module Memory Checksum Error

Did your scanner register the P0601 code? You must address it immediately. Here’s a guide that tackles the information you need for troubleshooting, including the code’s meaning, causes, and symptoms.

What Does the P0601 Code Mean?

Diagnostic trouble code (DTC) P0601 stands for “Internal Control Module Memory Checksum Error.” It is triggered when the powertrain control module (PCM) detects an internal problem, typically a failed Memory checksum test.

The PCM’s memory checksum test is performed regularly. It ensures the PCM’s reliability because all of the PCM’s short-term operational calculations and operating system software are stored in the memory. The PCM may not work properly if this part of its functionality has issues.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: Note that this code and similar P06xx codes can be triggered by poor performance equipment or by reflashing not authorized and cleared through the OEM.

A Closer Look at the P0601 Code

The P0601 code is set when there’s a problem with the internal microprocessor integrity conditions within the PCM. To be more specific, it is triggered when the PCM detects an error in the communication between its internal processor and internal memory modules. A data bus connects the various internal components within the PCM.

Communication packets that travel over the data bus contain what’s called a checksum — a mathematical operation that is used for error detection. If the PCM determines that the checksum has an unexpected value (or the PCM was unable to read its own flash memory), it will turn on the check engine light.

What are the Possible Causes of the P0601 Code?

There can be multiple potential causes for the code P0601. You must understand these causes first if you’re trying to learn how to clear code P0601. Here are the issues that can trigger the code P0601:

• Faulty control module
• Outdated control module software (not usually)
• Issues with the control module’s circuit, such as damaged wires or poor connections

What are the Common Symptoms of the P0601 Code?

The code P0601 can cause multiple problems involving various systems in your car. It could give way to other DTC codes as respective systems fail because of controller problems. On top of these, you may notice the following symptoms:

• Illuminated check engine light
• Engine stalling
• Difficulty in starting
• Vehicle will not start
• No symptoms at all

How to Diagnose the P0601 Code

Performing an accurate diagnosis is the key to resolving the P0601 code. However, this can be challenging because the code can be triggered by various issues. It’s the reason why many people leave this task to their mechanic.

Determined to diagnose the problem yourself? You can learn what the process might involve by researching P0601 code how-to videos and resources online. Make sure to focus on information that’s specific to your vehicle’s year, make, and model.

How to Fix the P0601 Code

Typically, you have to replace the ECM/PCM to deal with a code like P0601, and that usually requires programming, which you can’t do without the proper equipment.

Moreover, resolving the P0601 code is not a straightforward task because it can be triggered by various issues. The repair process may also vary depending on your vehicle’s make and model. For instance, the documented fixes for a P0601 code in a Toyota may not be as effective for a P0601 code in a Chevy.

Figure out the right fix using online auto repair resources and guides. Investing in an ALLDATA single-vehicle subscription, which provides comprehensive factory repair information, also helps.

Typically, you have to replace the ECM/PCM to deal with a code like P0601, and that usually requires programming, which you can’t do without the proper equipment.

– Richard McCuistian, ASE Certified Master Automobile Technician

Other Notes About P0601 Code

If there are other codes present along with the P0601, remember to fix the codes starting from the first one to get stored up to the last. If the P0601 code is the one causing all the other codes, it will come first in the list. Diagnosing, troubleshooting, and clearing it may get rid of the other codes stored in the system.

Get a Replacement Engine Control Module

A triggered P0601 code is the least of your worries when it comes to a faulty PCM. The PCM or engine control module (ECM) monitors and controls various engine functions, including fuel injection, ignition timing, and emission controls. If it fails, several of these functions could go haywire and make your vehicle unsafe to drive. Because of this, you should avoid driving until your ECM/PCM is fixed. Luckily, getting a brand-new ECM is fast and easy with CarParts.com.

CarParts.com offers a wide selection of high-quality ECMss, sourced from only the most trusted manufacturers in the industry. Thanks to our competitive pricing, you don’t have to worry about breaking the bank. We also have a price match guarantee policy. If you find a competitor selling the same product at a lower price, let us know, and we’ll either match or beat the price on the spot! If you’ve already purchased the ECM/PCM and find it being sold at a lower price elsewhere, we’ll work with you to issue a credit for the difference.

Don’t wait until your ECM completely breaks before replacing it. Check out our catalog of high-quality ECMs at CarParts.com and order one for your vehicle today!