Fix P0700 Obd2 Code: Transmission Control System Malfunction

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How To Fix P0700 Obd2 Code?
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If your car has the P0700 obd2 code, you’re going to want to fix it as soon as possible. P0700 code is quite a diagnostic trouble code for “Transmission Control System Malfunction”. This code indicates a problem with the transmission control system and turns on your car’s check engine light. Also, it can cause all sorts of problems with your car, including stalling and reduced performance.

Definition of P0700 Code

P0700 is a transmission system error (DTC) code that’s accompanied by various fault codes (also called a “box”) that appear on your car’s computer-based diagnostic system. You may experience it when driving a vehicle with an automatic transmission. 

Transmission Control System Malfunction: An electronic control unit (ECU) that’s electronic, usually located in the transmission. The powertrain control module (PCM) is designed to monitor and control the movement of the gear shifts in your vehicle.

P0700 Code Meaning

P0700 Code Meaning:

The P0700 code means the “transmission control system” has determined a problem with your transmission. This code will also turn on your car’s check engine light and illuminate the transmission symbol on your car’s dashboard cluster.

Now that we know what transmission code p0700 is let’s discuss its causes and symptoms.

OBD-II Code P0700: Symptoms, Causes & Diagnose

Causes of P0700 Code

The causes of p0700 can range from minor to severe like low or dirty transmission fluid, let’s discuss them all.

  • Faulty Transmission Control Module: This is a hardware failure and needs repair or replacement. The transmission control module (TCM) is to blame here. This rarely happens, but when it does, it must be fixed right away because the TCM is an important part of the transmission control system.
  • Faulty Shift Control Solenoid: Here, we have a problem with the shift control solenoid. The shift control solenoid is an electronic device in charge of moving the drivetrain into different gear ranges you find on your vehicle’s speedometer.
  • Faulty Transmission Sensor: There can also be a problem with a sensor. A sensor monitors different transmission parts and transmits the information to the TCM. These sensors can wear out with time, leading to transmission malfunctions.
  • Open or Short in the Wiring Harness: If you are experiencing any P0700 transmission codes, there may be an open or short wiring harness that runs between the TCM and the sensor. You can perform a visual inspection to fix it.

Symptoms of P0700 Obd2 Code

The P0700 code will set itself after the transmission control identifies the faulty sensor or component. Here are a few of the symptoms of p0700 error codes:

  • Shifting Problems: This is one of the most common symptoms of p0700. You’ll notice that it’s difficult to get full gear when you shift gears. The transmission will not select a lower gear than it’s already in. Also, pay close attention to the engine load and throttle position. 
  • Loud Clunking Sounds: The car will also clunk when you shift gears. It’s said that this Clunking sound is the “gear downshift” sound and that it can be loud enough to wake you up.
  • Engine Stalling or Dying: Your car may also stall while you’re on the road, and your vehicle will not respond. And, sometimes, the engine dies while driving. You would find that after restarting the car, it’s in the park position and that you have to start over again to drive it. 
  • Loss of Power: A serious p0700 error code can lead to loss of power and reduced performance. There are situations when the car will not accelerate or accelerate slowly.

If your car has a p0700, you need to address the problem right away. A serious transmission control error like this can cause poor gas mileage and permanent damage to your vehicle.

Diagnose P0700 Error Code

Tools you need to diagnose the p0700 code:

Here are some of the p0700 diagnostic scan tools that you can use to diagnose the P0700 transmission code:

  • OBD II Scanner: If you already have an obd2 scanner, consider using it. An obd2 scanner will retrieve all of your car’s fault codes and provide you with the code corresponding to your problem. 
  • OBD II Code Reader: This tool allows you to read the codes from your car’s computer. With this software, you can clear the fault codes in your system and scan them. 
  • Code Scan Tools: These codes are similar to the obd2 scanner but more advanced and used for modern cars. They have different modes for specific engine control module codes that software can access. 

Diagnosing Process

Here are a few of the steps to diagnose the p0700 transmission code:

  • First of all, use the obd2 scanner to retrieve the fault codes. It will show you why your car’s computer light is on, and it will provide you with the code. 
  • Next, you need to clear the codes from your car’s system so that your transmission control unit can properly run diagnostics on them. 
  • If it’s OK, you can do a diagnostic test to see if there is any problem with your transmission in real-time.
  • This is a process where you go to the transmission control module in the car’s transmission and then replace (if needed) the faulty sensor or component. 
  • Finally, check if there are any other problems with your transmission, like a break, slip, and noise at low speeds.

Common mistakes you must avoid when diagnosing P0700 code

Some people make a common mistake when diagnosing the p0700 code is that they replace the TCM. They will see that their car is not shifting properly, so they try to replace the TCM. But, this is not a good thing to do since you’re only wasting your money because a faulty TCM rarely happens.

How to fix the p0700 obd2 code?

How to fix p0700 obd2 code?

P0700 can be fixed by replacing the faulty sensor or component. And, if you are lucky, then maybe you can fix it with a software update. 

Also, find out what’s causing this problem. This is the most important step in fixing p0700. If you can identify the problem, you can fix the p0700 code.

Are there any other problems with your transmission? The chances are that if there is any other problem with your transmission, then it will also cause the p0700 obd2 code. So, it will be necessary to identify what’s causing it and fix it before further fixing the p0700 code.

Here are a few common steps to fix the p0700 obd2 code:

  • Replace the transmission control module (TCM)
  • Replace faulty wires, if any.
  • Restore the transmission valve body.
  • Replace a broken transmission shift solenoid


How to avoid the p0700 code?

If you want to avoid p0700, make sure that you are doing preventative maintenance on your transmission. If you’re doing a regular service, make sure that the fluid levels are ok. Your transmission would also benefit from a regular filter change if needed as well.

How much does it cost to fix the p0700 code?

In general, you can expect to spend hundreds of dollars fixing p0700. The amount of money you need to spend depends on how complicated the issue is with your transmission. And, if you are repairing yourself, then on whether you have the right diagnostic tools or not. Moreover, keep in mind that the cost of repair includes the cost of parts. 

Can I Fix P0700 Code Myself?

It’s recommended that you take your car to a reputable mechanic if you have a p0700 transmission code. This is because your computer control unit is faulty, and it will be difficult to make the diagnosis with your car’s transmission.