One of the most common problems with the Toyota Mirai is when it throws the P0700 trouble code. A trouble code is a code thrown out by an automatic transmission whenever it detects in the Mirai that there is an issue that needs your attention.
P0700: Transmission Control System Malfunction
In the case of the P0700, it is a general code. This means that it should be accompanied by some other code that should tell you the specific problem. It is a OBDII code and not just a Toyota specific code.
It is possible to get the P0700 code without any other code registering with your Toyota Mirai. If you get no other code it means that the transmission control circuit is malfunctioning. It is typically accompanied by other codes that’ll help shed light on the situation. When P0700 registers by itself can be tricky. Below you’ll find some of the common causes for the P0700 in the Toyota Mirai.
Mirai P0700 Code Definition
If you are scanning your vehicle right now, you should be looking for a second code that tells you what is actually wrong. Think about it like this.
- P0700 Says– “Hey there’s something wrong with this transmission.
- The Next Code(s) Say– “I’m the actual problem going on with the transmission. I’m what you’re looking for.”
The code will trigger the service engine soon light and may put the vehicle into limp mode. If your vehicle has gone into limp mode, it won’t come back out until the computer detects in the Mirai that everything is operating within normal specifications. Here’s more on what causes limp mode or how to fix limp mode.
Toyota Mirai P0700 Diagnosis and Symptoms
Since the P0700 doesn’t indicate a problem (it indicates that there is a problem) here are some common problems that will cause the code to be thrown, as well as some of the more common symptoms that something is wrong with the transmission.
Mirai P0700 Causes
- Bad transmission control module
- Faulty shift solenoid
- Low fluid
- Short circuit
- Bad valve body
Mirai P0700 Symptoms:
- Transmission having a difficult time shifting
- Limp mode activated
- Service engine soon light/transmission light
- Don’t get all the available gears
- Engine dying or running bad
What Does a P0700 Code Mean?
The code could mean any number of problems with the transmission. You may need to have the vehicle scanned further to figure out what is exactly wrong. Does the vehicle feel different? Or is it a situation where you wouldn’t know anything was wrong if the light wasn’t on.
Before you take it in to be looked at by a mechanic, you should at least check and make sure that the transmission isn’t low on fluid. If you have felt a change in the way the vehicle has been driving, make sure you know the signs of low transmission fluid…
You don’t want to end up spending a ton of money on taking it to a transmission repair specialist to find out that it could have been fixed just by adding some transmission fluid.
How to Check for the P0700 Code
The easiest way to check for any trouble code with a vehicle is to get a OBD2 scanner. They are cheap and worth their weight in gold. Otherwise, you can always take your car to the nearest discount auto parts store (Autozone, NAPA, etc..) and they’ll be happy to go ahead and run the test for you.
Remember, once you find the code, it’s not time to stop scanning. Let the scanner tell you all of the trouble codes that the vehicles ECM has and google them, just like you googled this one.
What To Do, or What Your Mechanic Will Do
The first thing that the mechanic will do is plug-in their OBDII scanner and see what code accompanies the P0700. As stated above, it can be anything. But, it’s often thrown when there are shift solenoid issues.
After that they’ll go ahead and clear the code and take the vehicle for a road test. This is normal. They want to recreate the problem. If it was a one-off thing, there’s no reason to replace the part yet. If there is a real problem, the code will almost certainly throw again immediately.
Before you take it in, make sure that you check the transmission fluid. It’s also a good idea to go ahead and have a look at the fluid itself. If the fluid is a rough color, or worse you find metal flakes in it, that can be a sign that the transmission is going out.
Here’s how to tell what the color of your transmission fluid is telling you.
The P0700 Code in the Toyota Mirai is almost always accompanied by another code. There are vehicle specific trouble codes and there are codes specifically for your manufacturer. Good luck fixing your vehicle. If there is anything that you would like to add, please leave a comment below.