Question about 2006 Mazda 3
I have a 2006 Mazda 3 2.3L with an error code of U0101: Lost Comm with TCM. It is not shifting correctly. The dash is not displaying what gear it is in and it shifts hard when you put in in Drive or Reverse. What is wrong and is it expensive to repair?
I can tell you with almost absolute certainty that a U0101 is the Trans control module either going bad, or is bad. It's possible the wires to it are shorted or burned through but very rare. If your car goes into "limp mode", where you seem stuck in 3rd gear, have a jolting reverse, can see no lights on gear position dash, with the AT light on, and the check engine light on, then that is it. You need to replace it. If you try to drive on it, it will eventually damage the transmission since there is nothing to let the transmission know when to shift based on the engine RPMs.
I know this because I just went through 1200.00 of unnecessary repairs with my daughters 2007 Mazda 3, including a new (used) transmission from the 3rd party warranty people (I had to pay diagnosis, and 1/2 labor, plus get a rental car for two weeks while warranty fools shipped their used tranny). But AAMCO did not diagnose the U0101 TCM error even though the code was there and not 5 miles after picking it up, the lights all came back on, and the car went into "limp mode" again for safety. That leads me to believe the original transmission was not even the issue at all. Who knows?
Either way, I researched this issue on the web and read dozens of similar issues, which all pointed to the TCM. So I took a chance and I went and bought a TCM at Mazda dealer and installed it myself in 25 minutes. They are not cheap - 680 bucks. You can get them online for about 200 less if willing to wait for delivery.
So far, car runs like a dream. Fingers crossed. Good luck to you all.
Posted on May 19, 2017
I got the code this morning but my car is shifting smoothly, i dont see a problem other than the check engine light being on. Do you guys think is going to be an expensive fix? I have a 06 mazda 3 with 87k miles
Posted on Jan 10, 2017
We have repair solution for all 2006-2012 Mazda3 and Mazda5 TCM's aka Transmission Control module.
Part numbers covered:
contact us at 818-429-4889
Posted on Nov 09, 2015
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