P1870 code — how to fix error fast

If you’ve retrieved the code P1870 on an OBD2 scanner tool, chances are that your vehicle seems like it’s losing power. This code can be more serious than you may assume, so the best move you can make is to explore a bit more on the P1870 code meaning.

This code is one of the most common ones and could happen to anyone, so our team of automotive experts wanted you to have all the details. We’ll help you deal with this code and find a way to overcome the problem that’s causing the code, as well as teach you ways of preventing the code from appearing in the future.

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What does the P1870 code mean?

The P1870 code is a transmission code that indicates there is an issue with the transmission control module. Specifically, the code indicates that the transmission is slipping, which means that the vehicle is losing power and not operating as it should. This can be a serious issue, as it can lead to safety concerns on the road.

To put it precisely, your car may not be as efficient when overtaking as it used to be, and it won’t behave the same way while driving at highway speeds. So, it goes without saying that this makes the vehicle much less safe and that’s why you should immediately find a solution for the problem.

What causes the P1870 code?

The code P1870 can be caused in a car for a variety of reasons. Some of the main symptoms that may be present with the P1870 code include a lack of power, difficulty shifting gears, and an illuminated check engine light. As you can probably guess, it all has to do with a different underlying issue, so here’s a list of all the potential reasons behind the code P1870:

Dirty or low transmission fluid

The transmission fluid helps to lubricate and cool the transmission components. If the fluid level is too low or if it’s dirty, it can cause the transmission to slip or not engage properly.

Problems with the shift solenoid

The solenoids are responsible for controlling the flow of fluid in the transmission. If they’re faulty, they can cause issues with gear engagement and cause the transmission to slip.

Worn-out clutch plates

The clutch plates are responsible for engaging and disengaging the gears in the transmission. If they’re broken or worn out, they can cause the transmission to slip.

Which car models does the P1870 code affect the most?

The P1870 code can appear in a wide range of car models, but it is most commonly found in General Motors vehicles. The reason why these particular models are more prone to the P1870 code is – they use a specific type of transmission that is more susceptible to slipping and other related issues. Some of the models that are most commonly affected by the P1870 code include:

• Chevy Silverado: One example of a car model that is more prone to the P1870 code is the Chevrolet Silverado 1500. This model has been known to experience issues with the transmission slipping or not engaging properly, which can trigger the P1870 code.
• GMC Sierra: The GMC Sierra 1500 may have transmission components or designs that make them more susceptible to transmission issues.

How to diagnose the P1870 code

Diagnosing the P1870 code requires specialized tools and equipment. The first step is to use a scan tool to retrieve the code and any additional codes that may be present. From there, you can apply some other testing methods to see what’s the real reason behind the code, so we suggest you do the following:

Check the fluid level and condition

Checking the fluid level and condition is another important step in diagnosing the P1870 code. Low or dirty transmission fluid can cause issues with slipping or engagement, so it’s important to ensure that the fluid level is correct and that the fluid is clean.

Do the transmission pressure test

A transmission pressure test can help diagnose issues with faulty solenoids or other internal components of the transmission.

Check the sensor and ECM readings

If other methods fail to identify the root cause of the P1870 code, a computer diagnosis may be necessary to analyze data from multiple sensors and components to pinpoint the issue.

How to fix the P1870 code

Fixing the P1870 code will depend on the underlying cause of the issue. So, once you’ve realized what’s causing the problem, you can move on with a solution and apply one of the following methods:

Top up or replace transmission fluid

If low or dirty transmission fluid is causing the issue, simply adding or replacing the fluid can often fix the problem. It’s important to use the proper type of fluid for the vehicle and to ensure that it’s at the correct level.

Replace worn-off solenoids

Faulty solenoids can cause issues with transmission engagement and slipping. They can often be repaired or replaced by a qualified mechanic.

Repair or fix broken clutch plates

Broken or worn-out clutch plates can cause issues with gear engagement and slipping. They can often be repaired or replaced by a qualified mechanic.

Replace a faulty torque converter

If the torque converter is faulty, replacing it could solve the issue with code P1870, but it takes checking the remaining components of the transmission system first. Torque converter replacement is one of the most expensive repairs you can do, usually ranging from $500 to $1000 depending on the make and model as well as labor costs.

How to prevent the P1870 code

Preventing the P1870 code involves routine maintenance of the affected systems. If you’ve had issues with this code before, here’s what you can do to reduce the chance of it re-occurring:

• Regularly check the transmission fluid
• Follow the manufacturer’s recommended maintenance schedule
• Check for any other transmission-related codes
• Frequently top up your transmission fluid and check its condition

If you can properly maintain your car, the code will be less likely to show up and that will help you as you won’t have to deal with expensive transmission repairs.

Our take

In the end, it all comes down to having the right information about the code and we truly hope that this guide was all you needed to find a solution. The worst thing that can happen if you are experiencing issues with the code P1870 is if the transmission starts slipping through the gears, which may compromise the output of each gear and the way your engine revs.

So, it’s better to immediately replace a faulty component to deal with code P1870 instead of waiting for it to lead to further transmission problems.