P0650 code — how to fix error fast

In the sea of error codes that may affect your vehicle, the code P0650 is one of the worst, and that’s not because it has some sort of devastating effect on your car’s engine. The P0605 code meaning has to do with warning lights that may appear on the dash, and it affects the way these lights are displayed.

So, it may lead to some pretty bad consequences if the warning lights fail to initiate, and that’s why our team decided to give you a hand. We’ll discuss everything you need to know about this code so you can get the diagnostic system of your car up and running again to warn you of low oil, engine issues, and other alerts.

Why you can trust REREV’s OBD2 code advice: Our automotive expert researchers with experienced mechanics undertakes a thorough research methodology to deliver precise insights on OBD codes. Find out more about OBD2 codes research process..

What does the P0650 code mean?

The P0650 code is a generic powertrain code, which means it can appear on any vehicle regardless of its make and model. The code indicates that there is a malfunction in the MIL circuit, which is responsible for turning on the Check Engine Light (CEL) on the dashboard. This means that if the P0650 code appears, the CEL won’t turn on, even if there are other issues with the vehicle.

The MIL circuit is a crucial component of the vehicle’s onboard diagnostic system. It monitors various systems and sensors and turns on the CEL if it detects any issues. Therefore, it’s essential to fix the P0650 code as soon as possible to ensure that the vehicle’s diagnostic system is working correctly.

What causes the P0650 code?

Whether it’s bad communication or an issue that goes deeper than the connections of the system, code P0650 can be caused by a variety of problems. We’ve got you covered on this one as well as we searched through the most common reasons behind this code and here’s what we came up with:

Issues with the MIL circuit

The most common cause of the P0650 code is a malfunction in the MIL circuit itself. This can be due to a faulty wiring connection, damaged wires, or a blown fuse. In some cases, the issue may be with the MIL bulb itself.

Malfunctioning PCM

The Powertrain Control Module (PCM) is responsible for controlling various systems in the vehicle. If the PCM is malfunctioning, it can trigger the P0650 code.

Faulty MIL lamp driver circuit

The MIL lamp driver circuit is responsible for turning on the CEL on the dashboard. If this circuit is malfunctioning, it can trigger the P0650 code.

Issues with the CAN bus system

The Controller Area Network (CAN) bus system is responsible for transmitting data between various systems in the vehicle. If there are issues with the CAN bus system, it can trigger the P0650 code.

Which car models does the P0650 code affect the most?

Since a reason behind this code can be as ordinary as an issue with wiring or connections, almost every vehicle can be prone to the code’s appearance. Our team wanted to go a step further and give you a list of the vehicle models that may be more exposed to this issue than others, and this is the list we’ve assembled:

• Cadillac CTS-V: The high-performance CTS-V model has been known to experience issues related to the P0650 code due to problems with the ECM and electronic throttle control (ETC) system.
• Buick Rainier: This mid-size SUV has been known to experience issues related to the P0650 code due to problems with the engine control module (ECM) and transmission control module (TCM).
• Cadillac SRX: This luxury crossover has been known to experience issues related to the P0650 code due to problems with the ECM and TCM.
• Isuzu Ascender: This mid-size SUV has been known to experience issues related to the P0650 code due to problems with the ECM and TCM.

How to diagnose the P0650 code

You may think that you need to have a specialized diagnostic kit to diagnose this code, but that’s luckily not the case. You can visit your mechanic prepared by getting to the bottom of the code yourself by using one of these recommended methods:

Use a diagnostic scanner

The first step in diagnosing the P0650 code is to use a diagnostic scanner to retrieve the code. The diagnostic scanner will provide specific information about the code, such as the freeze frame data, which can help identify the cause of the issue.

Plus, it won’t be a big hit on your budget if you get a portable low-cost OBD2 scanner which is enough to help you read the code.

Inspect the MIL circuit

The next step is to inspect the MIL circuit for any issues, such as damaged wires, blown fuses, or faulty connections. The wiring diagram for the MIL circuit can help identify any potential issues.

Check the PCM

If the MIL circuit is functioning correctly, the next step is to check the PCM for any issues. This requires specialized diagnostic tools and expertise.

Inspect the MIL lamp driver circuit

If the PCM is functioning correctly, the next step is to inspect the MIL lamp driver circuit for any issues. This circuit is responsible for turning on the CEL on the dashboard.

Check the CAN bus system

If everything else is functioning correctly, the final step is to check the CAN bus system for any issues. This requires specialized diagnostic tools and expertise.

How to fix the P0650 code

Depending on what the previous phase helps you discover about the root cause of this code, there are several ways to go when addressing the issue. Fixing the code won’t be as expensive as you may think if you properly diagnose the cause, so here’s what you can do to erase the code:

Repair loose connections

Sometimes, loose or corroded connections between the control module and other components can trigger the P0650 code. As such, one of the first things to check is whether all connections are secure and free from corrosion. If any loose connections are found, they should be tightened or replaced as necessary.

Replace the internal control module

If loose connections aren’t the issue, it may be necessary to replace the internal control module altogether. This usually involves removing the old module and installing a new one that is programmed to work with the vehicle’s specific make and model

Update the software or firmware

In some cases, updating the software or firmware in the control module can help resolve issues related to the P0650 code. This may involve reprogramming the module or updating it with newer software that addresses known issues.

Check the wiring and repair it if needed

Damage to wiring within the vehicle can also cause problems with the control module, leading to the P0650 code. If any damaged wiring is found during diagnosis, it should be repaired or replaced as necessary.

How to prevent the P650 code

Preventing the P0650 code can be accomplished if you get a complete understanding of what may initiate the code. We hope that this guide already gave you a better perspective on that, so here’s a bit of advice on how to prevent it from occurring again :

• Perform routine maintenance on the vehicle’s systems, including the MIL circuit, PCM, and CAN bus system.
• Take the vehicle for regular check-ups to identify any potential issues before they become major problems.
• Address any issues with the vehicle’s systems as soon as possible to prevent further damage.

Our take

The primary concern of our team was helping you deal with the code to avoid unpleasant situations like the “check engine” light not appearing on the dash if there’s a problem with engine performance or misfires.

We’ve given you an objective take on this issue and our experts feel like it should be enough to help you fix your car and avoid dealing with this menacing issue ever again.