P1635 code — how to fix error fast

The OBD2 code P1635 is one of the most common codes you may receive after a diagnostic scan of your car. It often appears if there’s an issue with the engine’s performance, but most drivers are unaware of the true P1635 code meaning and why it affects the engine.

In this guide, our team will deliver all these pieces of information to help you cope with the code as we go through the main ways of diagnosing, fixing, and preventing the code. We’ll also discuss some of the main causes that may potentially be triggering the code in your car, so stand by for instructions.

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What does the P1635 code mean?

The P1635 code is a generic powertrain code that is related to the body control module in your car. It indicates that there is a problem with the BCM or one of its associated components. Some of the most common symptoms of the code include the “check engine” light, failure of electronic components in the car, and decreased fuel efficiency.

If you notice any of these symptoms in your vehicle, it’s important to take your car to a qualified mechanic for diagnosis and repair. Ignoring the code can lead to more serious problems down the road.

What causes the P1635 code?

There are several possible causes behind the code P1635 in a car, and we wanted to give you a brief overview of each one to help you diagnose the issue in your car:

Faulty BCM

One of the most common causes of the P1635 code is a faulty body control module. If the BCM is not functioning properly, it may set this code as a way to alert you to the problem. In some cases, the BCM may need to be replaced to fix the issue.

Loose or damaged wiring

Loose or damaged wiring in the BCM system can also cause the code to appear. If the wiring is loose or damaged, it can disrupt the electrical signals that are sent between the BCM and other components in your car.

Failed relay

A failed relay in the BCM system can also cause the P1635 code to appear. Relays are responsible for controlling the flow of electricity between various components in your car. If a relay fails, it can disrupt the electrical signals and cause the code to appear.

Blown fuses

A failed fuse in the BCM system can also cause the P1635 code to appear. Fuses are designed to protect your car’s electrical systems from power surges and other issues. If a fuse fails, it can disrupt the electrical signals and cause the code to be triggered.

Which car models does the P1635 code affect the most?

While this code can be triggered in pretty much every vehicle, there are some models that seem to be more prone to it than others. These include the following models:

• Chevy Cobalt: This model has been known to have BCM failures that can cause various electrical issues, including the gauges not working and warning lights coming on.
• Cadillac Escalade: Some Escalade models may experience BCM problems which can cause issues with the power windows and locks as well as the lighting system.
• GMC Sierra: Certain Sierra models may also experience BCM failures that can cause electrical issues such as the gauges not working or warning lights coming on and that leads to the P1635 code.

How to diagnose the P1635 code

Diagnosing the P1635 code requires a thorough understanding of your car’s electrical systems and the diagnostic tools necessary to perform the job. Here are some steps that you can take to diagnose the P1635 code:

Look for other OBD2 codes

Before diagnosing the P1635 code, it’s important to check for other diagnostic trouble codes that may be related to the issue. Checking for other codes can help you pinpoint the problem and determine the best course of action.

Inspect the BCM wiring

Inspect the wiring in the BCM system for any loose or damaged wires. Repair or replace any wiring that is damaged or disconnected.

Check the relays

Check the relays in the BCM system to ensure that they are functioning properly. Replace any relays that are not working correctly.

Check the fuses

Sometimes, the issue with the code can be as simple as replacing a blown fuse, and that would restore the balance to the BCM in case a blown fuse is what caused the code in the first place. To diagnose the code this way, check the fuses within your car’s fuse box.

Use an OBD2 scanner

Use a scan tool to read and clear the diagnostic trouble codes. A scan tool can also help you identify any other issues that may be related to the P1635 code.

How to fix the P1635 code

Fixing the P1635 code depends on the underlying cause of the issue. Here are some potential fixes for each cause of the code:

Repair or replace a faulty BCM

If the BCM is the cause of the code, it may need to be replaced. This is a complex repair that should only be performed by a qualified mechanic.

Repair loose or damaged wiring

In case bad wiring and damaged connections have caused this code to activate, you’ll need to repair and replace the wiring and connections to get it fixed.

Fix a failed relay

Replacing a faulty relay could restore the power supply to the BCM and help fix and remove the code if the faulty relay caused BCM issues in the first place.

Replace a blown fuse

Finally, replacing a blown fuse can sometimes help remove the code and it’s one of the most common solutions for drivers that are facing a BCM power cut due to a blown fuse.

How to prevent the P1635 code

The best way to prevent the P1635 code is to properly maintain your car’s electrical systems. Here are some tips to help prevent the code:

• Regularly inspect the wiring in your car’s electrical systems for any signs of damage or wear.
• Replace any damaged or worn wiring as soon as possible.
• Check your car’s fuses and relays regularly to ensure that they are functioning properly.
• Schedule regular maintenance appointments with a qualified mechanic to keep your car’s electrical systems in good condition.

By following these tips, you can help prevent this code from appearing in your vehicle.

Our take

Overall, the code P1635 can be pretty difficult to repair in case you aren’t familiar with its meaning and the common causes that trigger it. So, with the help of this guide, you can hopefully save yourself the trouble with the code and remove it properly and on time to prevent severe engine issues.