P0700 code — how to fix error fast

If you experience problems with your transmission including rough shifting and hesitation, using an OBD2 scanner might indicate the P0700 code. While many drivers are confused by the P0700 code meaning, it mostly stands for a general automatic transmission problem. Well, we all have to agree on one thing – there’s no tampering with the transmission and risking it by driving a car affected by a transmission problem.

That’s why our team prepared this guide for you in which we’ll go in-depth into details about diagnosing the code, fixing it, and making sure it never happens again.

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 P0700 code mean?

The P0700 code stands for an overall breakdown of the automatic transmission. Well, it may not mean you have to necessarily rebuild it (which can cost up to $4000 depending on the model), but it’s a pretty serious thing. The issue could be registered within the transmission control module (TCM) which reports it to the engine’s computer.

When the ECU detects a problem with the transmission, it will illuminate the check engine light and store a corresponding DTC in its memory. The biggest problem is – this is a rather general code and further inspection may need to be done in some cases to determine the cause.

That’s why your mechanic may need to read the additional codes stored in the TCM and perform additional tests to determine the root cause of the issue. Common causes of a code include faulty wiring, a failed transmission control module, or other internal transmission problems.

What causes the P0700 code?

While the P0700 code is a general transmission control system malfunction code. there are some common reasons why it could trigger an ECU light. We’ll first discuss these in more detail before moving on to dealing with the threat:

Problems with the transmission control module

The TCM is an essential component of any car with an automatic transmission system as it controls the transmission components and provides necessary data to the ECU to control the shifting process. It’s not so uncommon to see a TCM completely fail, resulting in the chaos caused by a lack of proper signaling towards the computer.

For example, if the TCU is not sending correct signals to the ECU, the ECU may not be able to properly control the transmission. This could cause issues such as slipping gears, harsh shifting, or failure to shift at all, which could trigger OBD2 code.

Problems with the wiring

This one is directly connected with the previous reason since the wiring is responsible for information sharing between the TCM and the ECU. If there’s a problem with the wiring, it could directly affect the communication between these two modules and therefore allow inaccurate information to flow.

Internal transmission system problems

Sometimes there’s no helping it – you may simply have faulty inner components within the transmission system and it could only lead to more damage and further breakdown. Some of the main components that could go bad include the shifter solenoid, clutches, gears, and bearings within the transmission system.

Which car models does the code P0700 affect the most?

While the P0700 code can affect any vehicle with an automatic transmission, certain car models are more prone to this issue. Some of the cars that are known to have this problem include:

• Honda Accord: The seventh generation of the Accord equipped with a five-speed automatic transmission is known to have issues with the code.
• Chrysler Sebring: This car is equipped with a faulty automatic shifter that proved to be one of the worst automatic shifters out there with a frequently displayed code P0700.
• Nissan Sentra: This car is equipped with a faulty CVT transmission. While CVTs are designed to be more efficient than traditional automatic transmissions, they are also more prone to failure due to the complex nature of their design, leading to the code being activated.

How to diagnose the P0700 code

Diagnosing this code can be difficult, as it is a general code that doesn’t provide a specific diagnosis. To diagnose the code, a specialized diagnostic tool is needed, such as an OBD-II scanner. This tool can read the diagnostic trouble codes (DTCs) stored in your car’s computer system and provide more information on the cause of the issue.

Here are some of the ways you can diagnose the code other than using the scanner:

Check the transmission fluid level

Checking the transmission fluid level and quality may lead to an easier time getting to the bottom of the code. Low or dirty transmission fluid can cause issues with shifting and other transmission functions, which could trigger OBD2 code P0700.

Perform a transmission fluid pressure test

If there are no obvious issues with the transmission, you may need to perform a pressure test to evaluate the pressure of the transmission fluid and identify any issues with the pressure control solenoid or valve body.

Solenoid testing

If all other tests come up normal, you may need to test individual solenoids within the transmission to determine if they are functioning properly.

How to fix the P0700 code

Fixing the P0700 code depends on the cause of the issue. It all depends on the components that may need to be replaced since you’ll be likely looking at faulty parts that lead to the system’s failure. However, there’s also quite a bit about the exact parts that go bad, so here are some of the main general fixes and solutions:

Check for additional transmission codes

P0700 is a general transmission code, so it’s important to check for any additional codes stored in the transmission control module (TCM) to get a better idea of what’s causing the issue.

Inspect and fix the transmission wiring

Faulty wiring can cause communication issues between the PCM and TCM, which can trigger OBD2 code P0700. Inspect the wiring for any signs of damage, such as corrosion or fraying, and repair any damaged wiring as needed.

Top up the transmission fluid

Low or dirty transmission fluid can cause a variety of transmission problems, including triggering OBD2 code P0700. Check the transmission fluid level and quality, and replace it if necessary.

Inspect and replace the TCM

If there are no other codes stored in the TCM and all wiring and fluid levels are normal, it’s possible that the TCM itself is faulty. In this case, replacing the TCM should fix the issue.

The automatic transmission also uses transmission fluid which helps the torque converter translate the power onto the wheels. This fluid also helps ensure smooth shifting, so if there’s not enough fluid, you may need to fill up or perform a flush.

Your mechanic may also inspect the TCM in pursuit of additional codes that could shed some light on the nature of the issue, or replace the module itself if it’s faulty. Overall, it’s all repairable unless you let the problem persist for so long that the components get completely worn off which could lead to an expensive transmission rebuild.

How to prevent the P0700 code

There are some preventative measures that can help prevent the P0700 code from occurring. Routine maintenance should do it, so here are some of the ways you can avoid having to deal with the code:

• Change the transmission fluid regularly
• Check the fuel filter and its condition
• Have a torque converter inspected regularly
• Check the automatic transmission of your car in regular periods

Properly maintaining the affected system, such as checking for damaged wiring or corroded connectors, can also help prevent the code from appearing. If you suspect an issue with your car, it is always best to have it checked by a professional to avoid costly repairs down the line.

Our take

In conclusion, understanding the P0700 code can help you maintain your car’s health and avoid costly repairs. Knowing what causes the code, which cars are most affected, how to diagnose and fix the code, and how to prevent it can help you stay on top of your car’s maintenance needs.

Although you’ll probably have to entrust this process to an experienced mechanic, we still hope that this guide at least helped you diagnose the issue and get a sense of what needs to be done to fix it and prevent it in the future.