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Discussion Starter #1
how long does it take for the ecu to completely 100% reset if you cut off its power (via unplugging the ecu harnesses or pulling the efi and etcs fuse) I know it only takes less than a minute to pull the 2 fuses and it will reset the cel, but does it completely erase the logged fuel trims?

thanks!
 

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I usually try the disconnect the neg. pump the brakes, leave it for 15mins and the hook it back up, will clear the ecu, or so i have been told, but i get my cell back everytime, but mine is because i run Greddy EMU, and everytime i 2 step it i get the cell, cause it reads as a misfire. Try it if not go to lexus and get the cell read, fix the problem.
 

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Discussion Starter #7
thanks guys, but my question was if the ecu was completely disconnected from power. how long can the ecu itself hold the logged information? i know that you can unplug the ground from the battery and wait a few minutes but i want to know exactly how long the ecu can hold the information if it is unplugged and seeing absolutely no power. is it instantly, a few seconds or a few minutes?
 

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IF you read my post i told you how to COMPLETELY reset it. Noone knows the exact amount of time we just know 15 minutes works and pumping the brakes to drain any power its storing works. Doing this completely erases the stock fuel trims and places the ECU back in learn mode so everytime you do it you need to drive it like you stole it for about 300 miles
 

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Discussion Starter #9
OKCIS said:
IF you read my post i told you how to COMPLETELY reset it. Noone knows the exact amount of time we just know 15 minutes works and pumping the brakes to drain any power its storing works. Doing this completely erases the stock fuel trims and places the ECU back in learn mode so everytime you do it you need to drive it like you stole it for about 300 miles
gotcha thanks
you can also pull the efi and etcs fuse for 5 minutes in the fuse box located next to the battery . it will also reset the ecu and clear any cel's. its much easier and you wont lose and radio presets, clock time, and odo readings.
my question was how long can the ecu hold the information if it absolutely has no power, but i guess iam gonna have to go test it out myself with a obd scanner.

thanks guys
 

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gotcha thanks
you can also pull the efi and etcs fuse for 5 minutes in the fuse box located next to the battery . it will also reset the ecu and clear any cel's. its much easier and you wont lose and radio presets, clock time, and odo readings.
my question was how long can the ecu hold the information if it absolutely has no power, but i guess iam gonna have to go test it out myself with a obd scanner.

thanks guys
That was totally the fix I needed for my problem. Thank goodness got my baby back with some force!
Thank you
 
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Jason T Shaw
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