TCM Install - Mazda Instruction Guide | Free TCM Installation Tutorial

TCM Install Instruction Manual for Mazda Transmission Control Module & Re-Location To Brake Lines

Posted On: 07/21/2022 | Author: Kayla Wilson

We're so glad that we're able to help you with your Mazda TCM install! Whether you're repairing your Mazda transmission control module or using our exchange service program, our team is dedicated to making this process as easy as possible for you every step of the way, starting with our TCM installation tutorial!

Tools Required for Mazda TCM Install

• 10 mm short socket
• 10 mm deep socket
• 3/8" drive ratchet
• Small flat head screwdriver

Warning From Our Professionals!

*IMPORTANT* We strongly recommend disconnecting the negative battery terminal prior to removal any electrical unit. Doing so helps to prevent fuses/relays from blowing and fault codes/communication issues from occurring.

Important Message From Our Professionals! PLEASE READ

*IMPORTANT* One of the main reasons that the Mazda TCM fails is due to insufficient heat dissipation as they're fastened directly to the automatic transmission casing. When they're mounted directly to the transmission, the transmission control module overheats and eventually fails.

In order to extend the life of your rebuilt and repaired Mazda transmission control module, we highly recommend re-locating your TCM on the brake lines near the firewall with plastic zip-ties to secure it. This area has optimal airflow and will allow the Mazda TCM to operate under cooler temperatures.

Step-by-Step Detailed How-To Instructions for Mazda TCM Install

Before attempting to install your rebuilt, repaired, or new Mazda TCM, you need to know where to place it- especially for models such as the Mazda 3 Series and Mazda 5 Series. The battery box will need to be removed to gain easy access to the transmission control module area to minimize the risk of damaging parts during the installation process.

There are resources online and YouTube videos that show you how to access your transmission control module TCM without using all of the following steps to remove it, however, doing so greatly increases the risk of damaging additional parts only to save a couple of extra minutes. Our professionals here at UpFix highly encourage you to follow each step carefully to save you time, money, and patience as it will be done right the first time!

If you can't find the TCM placement for the model you're looking for, you can always call the Mazda dealership parts department to ask them where it is located in the vehicle and how many bolts you'll have to remove (generally 3-6 bolts).

There's really no need to purchase a TCM replacement, whether it's OEM or not. Instead, send your part in for repair as replacing it with a new part can add complication to the process for your vehicle dealing with a different TCM.

"Don't replace your parts- UpFix them!"

1. Relocate and Mount Mazda TCM to Brake Lines

Remember where the TCM was originally located when it was removed from our Mazda TCM Removal Tutorial?

Well, look directly behind and above where the original transmission control module placement was; you should see thick, sturdy, black wires. Surprise! These are your brake lines and where we strongly recommend you relocate and mount your rebuilt or repaired (hopefully not new) Mazda TCM.

You can use zip-ties (or any other material of your preference) to secure the Mazda transmission control module in place of the preexisting nuts.

2. Plug In TCM TCU Connector

You'll need to reconnect the Mazda TCM electrical connector to the transmission control module. Just push it in place and slide the rectangular, white lever down until you hear it click into place.

3. Re-Install Vibration Damping Weight

Replace the vehicle's vibration damping weight back onto the engine mount and secure it with the two (2) 17mm nuts.

4. Reconnect Battery Box Assembly

Next, you can slide the battery tray back into it's original location. It's easiest to insert the back end first (towards the windshield of the vehicle) and then wiggle the front in back in just as you did to remove it. Be careful not to damage any of the cables and wires as you complete this step.

Now you can secure the battery box compartment in place with the three (3) 10mm bolts.

Once this is complete, you can reattach the front portion of the battery box and reinsert the two (2) cables.

5. Plug In ECM ECU Connectors

Similarly to the re-connection of the TCM TCU electrical connector, you can push the ECM ECU electrical connectors back into their original location to the left of the battery box assembly. On both of these connectors, make sure to slide the rectangular, white levers down until you hear them click into place. In addition, after this has been completed, put the electrical connector covert back on.

6. Replace Battery Inside Battery Compartment

Then, it's time to place the vehicle's battery back into the battery compartment. You'll want to insert the battery with the negative terminal (black terminal) towards the rear of the vehicle and the positive terminal (red terminal) towards the front of the vehicle. This is very important to check and double check that you've completed this step properly!

Subsequently, if you're vehicle has a battery bracket that secures the battery, now is when you will reattach this to the battery compartment. Look closely at the bracket before you secure it into place as there are arrows embedded into the bracket to show you which direction is the front and where it should be placed. Secure this with two (2) 10mm nuts.

7. Reconnect Battery Terminals

To reattach the battery cables to the terminals, you will start with the positive cable (red cable) and secure it in place with a 10mm nut. Then, you will take the negative cable (black cable) and do the same thing.

Lastly, put the top battery cover back on and voila- you've just completed your Mazda TCM install! Congratulations!

How We Can Help | “Don’t replace your parts- UpFix them!”

Place your order TODAY for your fast and easy TCM transmission control module repair on our website listed below! Make sure you have your part numbers and fault codes from the diagnostic scan to share with us. Ensure you enter your personal information accurately so you can your part repaired and returned in 4-7 business days!

Once you receive your returned part, no additional programming will be required after the repair. Your TCM will be plug-and-play once re-installed back into your vehicle.

UpFix also offers a TCM Transmission Control Module Exchange Service for those that cannot go without their vehicles.

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