If the other vehicle was running and you only had 12.4 then something is awry

 

Where should I be on Voltage in order to read my ECU while my vehicle is off?

 

Yeah 12.4V is somewhat low. I say > 12.6V at least. Car would need to be in the "on" (not running) position quite a bit if you are gonna flash a new rom, as opposed just flashing say, a new timing map.

Troubleshoot the battery issue like the others have said and re-attempt. Good luck.

 

Are you successful at reading the ECU with 12.6v and having the vehicle at a stand still (not running) while using EcuFlash?

 

I have read my ecu one time and the battery was at 12.6V. I have an VIII though. Others have said the IX's are a little bit more sensitive regarding battery voltage, when flashing.

Both reading the rom and flashing a new rom will take more time for the car to be in the "on" position and it's safe to say the car probably needs more than 12.4V to complete both.

 

Thank you for the information. I will make an attempt to do this later today. Crossing my fingers that it actually works. I have a warrantee on the new battery so I will take it back to Autozone if it doesn't work.

 

Can anyone else chime in on what voltage they are running when car is not running and ignition on the 'on' position in order to use EcuFlash?

Im running the latest EcuFlash v1.44 on my Windows 8 laptop. I have an 06 Evo IX.

 

yes the 9 requires a lot of voltage vs the 8 to flash. Put the battery on a charger for around 6-8 hrs and let it charge. if it still cant flash after charging that long then just replace the battery because it should allow a flash if it can fully come back with a good healthy charge.

 

I just did a little test, with the key on and headlights and air on full blast I got 11.9 volts and it would not flash, I cut off the headlights and blower and battery voltage is reading 12.2v in evoscan. I flashed a brand new rom (long flash) and checked the battery voltage again afterwards and it was still 12.2, I then flashed the original rom back in it at 12.2v and it went through fine. Ecuflash 2.9
So it looks like your voltage should be fine. Is it cold where your at for some reason?

 

No it's 65 degrees outside and I have 12.42v when attempting to run EcuFlash but its version 1.44 I never seen a 2.9 version out there. What version of windows are you running?

 

Sorry I was looking at evoscan version, I'm using Version 1.42.2595

 

I was using a Windows 8 laptop with an open port USB 1.3.
I too have EvoScan with the latest version and I get the same results when I use that. Just doesn't seem to connect with the ECU.

 

What does voltage drop to with headlights and blower on?

 

90zcrex you made a good example of what works and doesn't with your Evo IX. Can someone else chime in on their results?

Thanks in advanced

 

I haven't tried that as of yet. I am waiting for my friend who has an older laptop so I can try it again. I have a turbo timer connected directly to my battery and I get very accurate voltage readings from it. So once my friend arrives I will make an attempt to log all that information. Hopefully I will be successful after this.