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Water.....sometimes waves
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I could go into a long winded plan to do what you are looking for. But,,,,,, you will be chasing your tail. Lots of hunting and reading schematics for proper voltages and wires. And then if you do get it to work, I suspect you will just get a "different" error code something like "ATF not at proper temp" since the ECU is not looking for this information yet the TCM is trying to send it, resulting in an error code, just like the no input error issue. I suspect the error codes pass from the TCM to ECU but not some of the actual sensor signals inputs/outputs. Not much you can do except block/pop the bulb and hope you don't have a REAL transmission temperature problem. I think if it were me, I 'd be looking for a proper ECU..............
 

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Water.....sometimes waves
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1,612 Posts
Yep I was confused. I do not believe the ECU (or ECM, the engine control unit or module) has much,if anything, to do with the TCU/TCM. I see in my schematics the TCM talks to the BIU (body integrated unit, but not the engine controller. Soooooooooo, you are correct it is a TCM issue. The TCM is not sending the proper voltage (should be 5V) to that sensor. You either have a bad TCM or the sensor (or wires to it) itself is bad. Have you tried replacing the sensor itself or checking for 5V at one of the wires to it?

Should say I am looking at 2015 schematics and assuming the arrangement is "similar."
 

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Water.....sometimes waves
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1,612 Posts
Sorry, can't help you there. But I do think the trans temperature light blinking has nothing to do with the ECU (assuming ECU is the engine controller in your car.)
 
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