Friends ECU flashed once to SD (was cold out, flash completed). Car wouldn't start, so tried to flash back to stock, wouldn't flash. Fast forward a few weeks, and flashed the ECU in my car (test to see if it'd work). Plugged his ECU into my car an hour later, and it wont flash.

Sound like a bricked ECU? If so, is there a way to unbrick it like the Evo X's have?

 

you sure your battery is charged well? the ecu will halt read and write processing to it from my understanding if the battery is to low of voltage in defense against corrupting the flash process.

also keep in mind each evo has a custom immobilizer system onboard, so you cant just swap the ecu and expect the car to fire up without changing that code to match the specific cars immobilizer.

 

The battery voltage is critical as posted above, attach a jumper pack and try and reflash again. Failing getting it to flash back, save a log from Ecuflash of the failed reflash and post it up.

 

I remember doing an E9 where I wrote a flash on then realised I'd forgotten to swap over the immobiliser code. The only problem was that because the car wouldn't start I didn't have enough battery voltage to reflash it with the map with the correct code in it.

In the end I connected up a jump pack to it and it flashed over all OK.

Andy

 

Shoulda been more clear.... Immobilizer is disabled on both, and I had a charger hooked up when I tried to flash.

And it's not that it won't start. It won't even flash, within an hour of it flashing on my ecu.

 

Try and flash it again using Ecuflash, when it fails select 'file > save log as' and post the log up. One other thing to check is the init code of the rom has not been altered, so you will either need to run unlocker or reset it back to 0001.

 

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