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2011 Mazda5 - Check Engine light, AT light, AND TSC/DSC light

Hi Guys,
2011 model, 2000cc, petrol, automatic. got it new from the dealer. 140K km now. no problems at all. see the garage once a year for periodic maintenance. the only complain ... the car is very low ... when you go off roads you must be careful. I'm emphasizing all this "goods" in contrast to my previous Volvo XC70 cross country !!!, so nice and so !!!! unreliable.
Last Friday night, started the car and got the 3 orange lights on : Check Engine, AT and TSC/DSC. Hallelujah ...
the transmission was at some sort of "safe" mode, (3rd gear only), no indication ... P/R/D on the dashboard, start driving carefully ... maybe its a glitch and the lights will go away ... but no!, it was stable like a rock. although the lights are orange, I decided not to drive home and call the towing service next day. a side note : there is no chance that all 3 systems will stop working together ...probably there are certain fault conditions, that when happen, force the other two lights to turn on too.
Next day at the mechanic shop : connect to diagnostic system, the car trow the "famous" U0101 code that means no connection with the TCM (Transmission Control Module) which probably explains why there were no P/D/R indications on the dashboard and why the gear was at safe mode. the guy had a used (working) TCM, (claim to disassemble it from an 80K km car), he removed my TCM and installed the used one, very complicate work ... under the battery ... put all together (no screws left ...;)) and started the car. all works smooth, no lights are on.
I hope it will stay so.
It appears that the chip in this module failed. this can happen as every semiconductors that is subject to stress (voltage) will break over time. now, you have to decide what is the best option, (assuming getting a new $1000+ module from mazda is not an option) getting a repaired module with a new chip inside - zero age, or getting the used one, non zero age that might break in the future ? I decided for the used one, as the repaired option may have a sealing issues (they take out all the silicon to be able to take out the broken chip ... and then seal it again but not as it is done in the factory).
I paid ~$500 in my country for the whole event.
What do you guys think ?


2010 Mazda 5 Sport
You are correct on the lights. Many cars will switch off the traction control and other systems related to the failed part. The error codes are all that really matter. Why cars don't actually display the code AND A BRIEF DESCRIPTION is a rant for another day.

I specifically snagged a manual transmission car when I saw a used one reasonably priced. So I don't have this issue. Mine will be a new clutch when my teenager is done thrashing it.

BUT if I did have an automatic with a failed module, I would definitely go the remanufactured route. At least you will get a module that has been tested and should have at least a 30 day warranty. Junkyard modules might work...but you might be doing the job twice.

I'll say that IC chips almost never fail. I would say that the failure will be with another component. Probably it's a capacitor or a crappy soldering joint or simply a bad circuit design that blows the IC. People blame the chip when it is some other problem on the board. But I suppose there are exceptions.