Automotive Forums  Where Car Enthusiasts Go to Discuss Cars Online

I'm buying a used (OEM)ECU for my 1999 prerunner, and I think I can install it myself, but my mechanic said that if i didn't rebuild it with the same into, I'd have to take it to the toyota dealership to have it reset?  I was hoping someone could help me figure out if I could buy a used ecu, replace it with mine and make the truck work correctly. Thanks in advance for the help!  

most newer cars can use generic ECUs .. that are individually programmed for specific cars...

prior to being able to do this... mechanics had to swap chips in the computer to make it work...

flash programming allows the manufacturer to do tiny changes to the program.. with just a reflash that can be done at dealers or some better equipped shops..

if you live in a smog inspection state also..

you will need to have the VIN number and the mileage programmed into it with a scan tool at time of installation..
or it won't pass many states smog inspection.. which requires the smog machine to be plugged into the obd2 port..

Warning...  please verify that the computer is BAD before swapping it out...
there are thousands of pages of trouble shooting that needs to be done with a scan tool first..

after reading the TSBs on the car..  to see if similar problems can be found... tsb titles can be read at alldatadiy.com  lower right corner of their front page.. and the title listings are free... if you find one that you need to read.. copy the numbers and the date from it..  most dealer ships and some mechanics will look them up for you ..  

oh.. as for resetting it...  to change between cars... i don't know if thats easily possible..

please hang on to your old ECM.. don't exchange it.. if you are buying a used one..  

if you give them your used one..  they just sell it to core suppliers or scrap... you will be up a creek if it does not work in the long run...