2024 CX-5 TCM / Transmission Failure

[yrwei52]

Here’s a 2024 Mazda CX-5 with only 400 miles was having TCM or transmission failure. Unfortunately the entire replacement transmission shipped all the way from Japan came with a “refurbished” TCM (chip shortage?) which didn’t work. The dealer had to re-order it again from Japan and waiting! How about do a better quality control job Mazda?

 

[sinistriel@]

I would bet that there is much more going on behind the scenes than he is being told. The TCMs are new from Mazda and not reman. Each TCM is matched with the solenoids and are flow tested with each other, this is why Mazda does not sell the TCM, solenoids or valve body separate from each other but as a "mechatronics" unit.

 

[paris1]

Jesus; this guy needs to learn how to edit himself! I lost interest in it a third of the way through.

 

[jbsx]

So not communicating with the main computer because of maybe a buss problem?
Who knows. It's all second hand info.

 

[Oceantango]

I would bet that there is much more going on behind the scenes than he is being told. The TCMs are new from Mazda and not reman. Each TCM is matched with the solenoids and are flow tested with each other, this is why Mazda does not sell the TCM, solenoids or valve body separate but as a "mechatronics" unit.

So if you ever had a TCM failure you would need to replace complete transmission or is it an internal part of transmission?

 

[sinistriel@]

So if you ever had a TCM failure you would need to replace complete transmission or is it an internal part of transmission?

No you can order a new TCM separate from an entire transmission for it and replace it if needed. I've ordered several for various Skys over the years when they have been needed and for R&D purposes. You just can't buy the TCM by itself.

 

[paris1]

No you can order a new TCM separate from an entire transmission for it and replace it if needed. .... You just can't buy the TCM by itself.

Huh?

 

[Mach1tosh]

I'd be banging on someone's desk for a new car to match the broken one.

 

[wlong01]

I'd be banging on someone's desk for a new car to match the broken one.

Damn tootin.

 

[sinistriel@]

Huh?

Sorry I am multitasking poorly right now lol.
To get the TCM from Mazda you need to order the entire "mechatronics" unit. It goes by a few names depending on who you are talking to but can be called a valve body, mechatronics unit, Mazda lists it as "Valve, Control" in most of the parts catalogs. It consists of a traditional valve body including solenoids, wiring harness and TCM. Mazda sells it as an entire unit because it uses direct linear solenoids that have flow rates that vary between solenoid. When Mazda produces the valve bodies they flow each solenoid to each valve body and write that information into the TCM so it can correctly control each solenoid. First picture is the whole unit, second picture is the TCM portion and then third is the solenoids.

Mazda will sell you the valve body separate from a new transmission, my reply should have read that I've ordered the mechatronics assemblies.

 

[AL Cx5]

Sorry I am multitasking poorly right now lol.
To get the TCM from Mazda you need to order the entire "mechatronics" unit. It goes by a few names depending on who you are talking to but can be called a valve body, mechatronics unit, Mazda lists it as "Valve, Control" in most of the parts catalogs. It consists of a traditional valve body including solenoids, wiring harness and TCM. Mazda sells it as an entire unit because it uses direct linear solenoids that have flow rates that vary between solenoid. When Mazda produces the valve bodies they flow each solenoid to each valve body and write that information into the TCM so it can correctly control each solenoid. First picture is the whole unit, second picture is the TCM portion and then third is the solenoids.

Mazda will sell you the valve body separate from a new transmission, my reply should have read that I've ordered the mechatronics assemblies.

Gosh, you wonder how the other millions of TCU and solenoids transmissions worked!

Seems like Mazda has made this process overly complicated. First I've heard that solenoids flow that much different for on another....

Good info, thanks

 

[sinistriel@]

Gosh, you wonder how the other millions of TCU and solenoids transmissions worked!

Seems like Mazda has made this process overly complicated. First I've heard that solenoids flow that much different for on another....

Good info, thanks

Its become a quite common practice in the industry to flow linear solenoids and let the TCM know the characteristics. It allows for very precise control of clutch application that was not possible in older units.

GM for the 6L/6T have them integrated into the TECHM and that carries the rates. 8L90 and the 10L family use a system called PUN/TUN that you purchase the valve body and input the solenoid numbers into the TCM for correct control.

Chrysler moved the TCC solenoid out of the solenoid pack in the 68RFE in 19+ to its own with a QR code that contains the flow rates that you have to input or TCC will not function. All the ZF8/9 speeds have it baked into the mechatronic unit.

Ford uses a similar system as GM for 6F/6R and 10R families.

Toyota has used it for some time as well on some of their units.

Overall its a great system from a control point, Mazda has just unfortunately chosen to follow the part of the industry that does not allow for user input of a new solenoid number.

 

[AL Cx5]

Its become a quite common practice in the industry to flow linear solenoids and let the TCM know the characteristics. It allows for very precise control of clutch application that was not possible in older units.

GM for the 6L/6T have them integrated into the TECHM and that carries the rates. 8L90 and the 10L family use a system called PUN/TUN that you purchase the valve body and input the solenoid numbers into the TCM for correct control.

Chrysler moved the TCC solenoid out of the solenoid pack in the 68RFE in 19+ to its own with a QR code that contains the flow rates that you have to input or TCC will not function. All the ZF8/9 speeds have it baked into the mechatronic unit.

Ford uses a similar system as GM for 6F/6R and 10R families.

Toyota has used it for some time as well on some of their units.

Overall its a great system from a control point, Mazda has just unfortunately chosen to follow the part of the industry that does not allow for user input of a new solenoid number.

Thanks for the explanation.

Transmissions are way more complex than engines and have gotten even more complex!

Are there any standalone TCUs for these trans? I'm using a standalone on a Nag1 that greatly increases it's capability.

 

[sinistriel@]

Thanks for the explanation.

Transmissions are way more complex than engines and have gotten even more complex!

Are there any standalone TCUs for these trans? I'm using a standalone on a Nag1 that greatly increases it's capability.

No standalone TCMs and would be hard to get one to work with how it integrated it is, things like the input and output speed sensors are molded into it. I'm waiting for TCM access, there are a few companies working on making it happen and I am involved with one of them to see what we can make happen.