P1815 code — how to fix error fast

If you receive the code P1815 from a diagnostic scan of your car, it can be the first sign of an issue with your car’s crucial systems. In this case, it’s precisely an issue with the transmission, and it takes some knowledge of the P1815 code meaning to overcome such issues.

While it can often lead to serious gearbox faults, it’s not a code you want to leave active without an instant reaction. So, our team wanted you to have all the information on the code P1815 including the possible causes of this code, ways of diagnosing it, and possible solutions that we’ll present in this guide.

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What does the P1815 code mean?

The P1815 code is a DTC that is related to the transmission range selector position switch. This switch is responsible for indicating the position of the transmission range selector, which is used to select the desired gear or mode of the transmission.

When the ECM (engine control module) detects that there is an issue with the transmission range selector position switch, it will trigger the P1815 code. This code indicates that there is an issue with the switch, which can cause a number of symptoms and consequences.

Some of the symptoms of the code include harsh shifting, transmission slipping, and difficulty shifting gears. In addition, the transmission may fail to engage or disengage properly, and the vehicle may not start at all.

What causes the P1815 code?

Since the code is mostly triggered by a faulty transmission range position switch, most drivers think that replacing it will fix the code. However, it often takes more than that to remove this code properly, and we’ll go over all the possible reasons and faulty components that may need to be repaired to fix the code:

Faulty transmission range selector position switch

The most common cause of the P1815 code is a faulty transmission range selector position switch. This switch may fail due to wear and tear or damage, which can cause it to send incorrect signals to the ECM.

Wiring issues

Wiring issues can also cause this code to appear. If the wiring that connects the transmission range selector position switch to the ECM is damaged or corroded, it can cause the switch to send incorrect signals and trigger the code.

ECM malfunction

Sometimes, the code may be triggered due to a malfunction in the ECM. This can occur if there is a software issue or if the ECM itself is faulty.

Which car models does the P1815 code affect the most?

The P1815 code can affect a wide range of car models, but there are certain models that may be more prone to encountering this code. These models include:

• Chevrolet Traverse: Some Chevy Traverse models have been reported to have problems with the transmission range sensor circuit, which can cause the car to shift erratically or hesitate during acceleration. This issue may be caused by corrosion or damage to the wiring or connectors.
• GMC Acadia: The Acadia may also be prone to issues with the transmission range sensor circuit. Symptoms may include rough shifting or stalling. This issue may be caused by damage to the wiring or connectors.
• Buick Enclave: Some Buick Enclave models have been reported to have problems with the transmission range sensor circuit, which can cause the check engine light to come on and affect the car’s performance.

How to diagnose the P1815 code

Diagnosing the P1815 code requires specialized tools and equipment, as well as a thorough understanding of the transmission system. However, you don’t need to be a professional mechanic to do some tests, as we’ll show you in a bit:

Scan the vehicle for DTCs

The first step in diagnosing the code is to scan the vehicle for any DTCs that may be present. This can be done using an OBD-II scanner, which will provide a list of any codes that are present in the system.

Check the transmission range selector position switch

The next step is to check the transmission range selector position switch for any signs of damage or wear. This can be done by visually inspecting the switch and testing it with a multimeter.

Check the wiring

If the switch appears to be in good condition, the next step is to check the wiring that connects the switch to the ECM. This can be done by inspecting the wiring for any signs of damage or corrosion and testing it with a multimeter.

Check the ECM

If the switch and wiring appear to be in good condition, the next step is to check the ECM for any signs of malfunction. This can be done using specialized diagnostic equipment that can communicate with the ECM and provide detailed information about its operation.

How to fix the P1815 code

Now that you’ve set up a proper diagnosis of the code, you can make use of the following actions to solve the issues and finally fix and remove it. You can start with one of these solutions depending on the exact reason that made the code go off in your car in the first place:

Replace the transmission range selector position switch

If the switch is found to be faulty, it will need to be replaced by removing the old switch and installing a new one to make the code go away.

Repair the wiring

If the wiring is found to be damaged or corroded, it will need to be repaired or replaced. This can be done by splicing in new wiring or replacing the entire wiring harness, and it’s best to leave such a task to a trained professional if you never dealt with automotive wiring or connections before.

Replace the ECM

If the ECM is found to be faulty, it will need to be replaced. This is a more complex repair that should only be attempted by a qualified professional.

How to prevent the P1815 code

Preventing the P1815 code requires proper maintenance of the transmission system. The following are some preventative measures that you can take:

• Regularly inspect the transmission system for signs of wear and damage
• Perform routine maintenance on the transmission, such as changing the fluid and filters
• Avoid driving in extreme conditions, such as extreme heat or cold
• Drive the vehicle in a manner that is appropriate for its intended use

By following these preventative measures, you can help to avoid encountering the P1815 code and ensure that your vehicle’s transmission system remains in good condition.

Our take

In the end, the code P1815 proves to be one of the trickiest OBD2 codes to diagnose and fix, but with the help of this guide, you’ll now be equipped to remove it. Make sure to also consider the preventive measures listed in this guide, as these can help figure out a long-term solution for the code.