I have an Evo 9 ECU that I have flashed to a couple of times. Now I suddenly cannot flash to it. It still works (drives the car), I can datalog but I just cannot read or write to it.

I tried it in another car and I cannot read/write. My laptop/cable work for other cars/ECUs so I figure it must be the ECU.

The only thing I have not tried is seeing if I can read/write to another 9 ECU (all the others I have tried have been 8 ECUs). Maybe my ECU Flash is somehow corrupted when reading/writing to a 9?

If the ECU is the problem is there anything I can do? I tried using ECU unlocker for the hell of it but that didn't work either.

Thanks.

 

Check the battery level? Try to start the read/flash with the car running after driving for 10 min?

 

Are 9 ECUs more finicky with regards to battery voltage?

 

AFAIK yes. The people that usually have the voltage problems are the IXs. If you search around you should come across this topic. I think last time someone also pointed out that the newer versions of ECUFlash have a check for voltage written in the program so between the two of them....

 

yeh battery too low.

charge it overnight or go for a drive