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does anyone know much on this TCM issues with mazda3 2.3l automatic when the AT light comes on and the car does not run at full speed, and won't shift gears.
And if so where and how did you fix this problem?
 

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Demon Spawn
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that's a very vague description, tranny code? any lights on other than AT light? what diagnostic codes do you get?
 

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I know that some cars have had the problem. I bought an 08 3s recently with 107k miles. The previous owner had the TCM replaced at a dealer for $1000.00! Now that I own the car and have been working on it I can say it’s an easy repair. Remove the battery and tray and it’s right there.
 

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I had these symptoms and replaced my TCM with a refurb from a guy on eBay in California. Complete success, and a pretty easy repair. I figured the $250 I spent on that was a good bet to fix the problem, but in the event something else was the culprit it was also a good signal to a tranny shop that they shouldn’t try to bluff me with a wholesale transmission replacement.
 

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I know that some cars have had the problem. I bought an 08 3s recently with 107k miles. The previous owner had the TCM replaced at a dealer for $1000.00! Now that I own the car and have been working on it I can say it’s an easy repair. Remove the battery and tray and it’s right there.
Got a similar problem on an 04 I tinker with. TCM is not under the battery. Have had advice that it could be on rear of transmission, or under the console. One parts person suggests there is no TCM on my car. Anybody had any luck with the older models
 

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Got a similar problem on an 04 I tinker with. TCM is not under the battery. Have had advice that it could be on rear of transmission, or under the console. One parts person suggests there is no TCM on my car. Anybody had any luck with the older models
Said parts person shouldn't make statements when he doesn't know the facts. The TCM is mounted to the top of the transmission, just below the battery. Theories discussed by those of us who have replaced the TCM regarding why the TCM fails is because it is not shielded from the heat generated by the transmission. The TCM acts as a radiator, which it is not designed to do. Some people have postulated building a custom shield that acts like an insulator would protect the TCM.
 

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Said parts person shouldn't make statements when he doesn't know the facts. The TCM is mounted to the top of the transmission, just below the battery. Theories discussed by those of us who have replaced the TCM regarding why the TCM fails is because it is not shielded from the heat generated by the transmission. The TCM acts as a radiator, which it is not designed to do. Some people have postulated building a custom shield that acts like an insulator would protect the TCM.
Thanx much Gary. Will check the top of the transmission and let you know. Thought the parts person got tired of loolong
 

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Thanx much Gary. Will check the top of the transmission and let you know. Thought the parts person got tired of loolong
If you have the manual you can see it's not too hard to locate. PM me if you need a copy and I will send you a link to my Google Docs folder. If you search the site, you will see a lot of info about the TCM. The 2.0L vehicles have the TCM integral to the PCM. That might be what the parts person was thinking. It's very easy to replace, and don't believe anyone who tells you it has to be programmed to play nice with the vehicle's security system.
 

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Does anyone know if a 2.3L 2006 TCM works in a 2007-2009 2.3L? I see the 2006 have a different part number (L32) versus the (L34) of the TMC units found in 2007-2009.

I have a junk yard TCM from a 2006 and wonder if it could work in my 2008. Any knowledge?
 

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If you have the manual you can see it's not too hard to locate. PM me if you need a copy and I will send you a link to my Google Docs folder. If you search the site, you will see a lot of info about the TCM. The 2.0L vehicles have the TCM integral to the PCM. That might be what the parts person was thinking. It's very easy to replace, and don't believe anyone who tells you it has to be programmed to play nice with the vehicle's security system.
Could not find it on the top of the transmission.Sure would appreciate copy of that manual just not sure how to PM you. please advise
 

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Could not find it on the top of the transmission.Sure would appreciate copy of that manual just not sure how to PM you. please advise
I sent you a PM. Check your alerts at the top right corner of the screen. Your avatar should have a small red dot indicating a notification.
 
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