Computer Systems Engineer on the reflash

stingray719

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I have been flashing computers since the mid 90's. Back then if the flash failed you bought a new motherboard, but newer computers automatically save the old flash and revert if the flash fails. The point I am making is a failed flash is not rare that is why those safeguards are put in. The 2007 Phazer issue was not reflashed Yamaha sent out new ECU and I am certain it was for this reason. Having non computer people reflash ECU "in the field" would not be my suggestion either.

When flashing a computer a few things are critical. First your computer power must not be disturbed. Second if flashing remotely like the Viper is being done nothing else should be running in the background.

So does your dealer use a laptop that has nothing on it besides the Yamaha flash? Does he reboot the laptop between flashes? I ask that because when they flashed my first Viper it went fine, when they tried to flash the second it did not recognize my VIN and they were going to enter the VIN manually. I insisted they reboot the laptop and it recognized the VIN. So something I do not know as they were hesitant to let me play with there laptop, is if the flash can be forced a second time? If so any of you with issues after the flash should be able to have it redone. Cannondale27 do you know?
 
Wow maybe more to the story
 
I will find out for sure but I believe it can be reflashed again. Not with the old code though. Once gone it is gone. I do not like the process. It is being done through the Internet. It could be corrupted from that. The code should be on a disc and given to the dealers. I know with the Cannondales which we all could fully map and reload HEX codes even the simple fuel maps could not be trusted when downloaded from Internet. We were given the actual HEX codes because sometimes during simple downloads like a throttle cal the whole hex code could be corrupted and you would be dead in water.
 
I will find out for sure but I believe it can be reflashed again. Not with the old code though. Once gone it is gone. I do not like the process. It is being done through the Internet. It could be corrupted from that. The code should be on a disc and given to the dealers. I know with the Cannondales which we all could fully map and reload HEX codes even the simple fuel maps could not be trusted when downloaded from Internet. We were given the actual HEX codes because sometimes during simple downloads like a throttle cal the whole hex code could be corrupted and you would be dead in water.

Yes if it is a live update from the internet and not a file fully downloaded and bit checked you will have some corruption on some. We NEVER install a file remotely but download the entire file and install.
 
Not sure if the file is actually on the computer and you are just going on line for ID purposes?
 
I reflash vehicle ECU's all the time for Toyota. Not sure if the process for Yamaha is the same but we also do ours through the internet. The computer first reads the ECU's program number to see if it requires a reflash. It then downloads the correct flash to a file. If it does not need the flash or if the number is correct then the process ends. After the process is over it reads the number again to see if the reflash was successful. The key is cycled ON/ OFF between the beginning then again after completion. 12.5volts at the battery is a MUST. If your battery is marginal a battery charger MUST be used DURING the process! The importance of proper battery voltage during the process cannot be overstated. Maybe they are not seeing if the flash was successful or trying to flash with batteries in less than full state of charge?
 
I reflash vehicle ECU's all the time for Toyota. Not sure if the process for Yamaha is the same but we also do ours through the internet. The computer first reads the ECU's program number to see if it requires a reflash. It then downloads the correct flash to a file. If it does not need the flash or if the number is correct then the process ends. After the process is over it reads the number again to see if the reflash was successful. The key is cycled ON/ OFF between the beginning then again after completion. 12.5volts at the battery is a MUST. If your battery is marginal a battery charger MUST be used DURING the process! The importance of proper battery voltage during the process cannot be overstated. Maybe they are not seeing if the flash was successful or trying to flash with batteries in less than full state of charge?

Sounds like exact same process.
 
I reflash vehicle ECU's all the time for Toyota. Not sure if the process for Yamaha is the same but we also do ours through the internet. The computer first reads the ECU's program number to see if it requires a reflash. It then downloads the correct flash to a file. If it does not need the flash or if the number is correct then the process ends. After the process is over it reads the number again to see if the reflash was successful. The key is cycled ON/ OFF between the beginning then again after completion. 12.5volts at the battery is a MUST. If your battery is marginal a battery charger MUST be used DURING the process! The importance of proper battery voltage during the process cannot be overstated. Maybe they are not seeing if the flash was successful or trying to flash with batteries in less than full state of charge?


Yes what he said.

I do a lot of ECM reflashing on GM. Most of it on the bench with a 12vDV regulated power supply and some in vehicle. Checksums are used to verify the integrity of the data on the ECM. There is no almost or corruption possibility in most modern systems. Reflashing the same data makes no difference. Some if interrupted will "brick" the ECM making it useless.

Some ECU's consume a lot of power while being programmed. With the frail nature of the snowmobile battery, I would think that there would be a suggestion made to have a second battery connected or some other regulated charge system.
 
Dealer told me once the reflash is done they can not do it again. I have to wait for them to release another update or reflash.
 
Dealer told me once the reflash is done they can not do it again. I have to wait for them to release another update or reflash.

Thats what our tech said also. There is a way though. When we lost the whole thing on the Cat they downloaded a whole new program. Basically a reboot of the ECU itself. Took some time on phone though. Also if one of those spring sleds which required a registration code AC can for sure handle it. Might be worth trying a AC dealer with good contacts at AC. Did I just say that!
 
Dealer told me once the reflash is done they can not do it again. I have to wait for them to release another update or reflash.

That has to be something they build into the software........mind you I've been retired for 13 yrs but I did spend almost 40 yrs as a system designer, etc.........ECU's are nothing more than what is called a PROM..........Programmable Read Only Memory.........the operative word being Programmable.......unless somebody has figured out a way to change the hardware in the last decade plus, there's no way to block a complete reflash except by software based lock of some kind..........
 
That has to be something they build into the software........mind you I've been retired for 13 yrs but I did spend almost 40 yrs as a system designer, etc.........ECU's are nothing more than what is called a PROM..........Programmable Read Only Memory.........the operative word being Programmable.......unless somebody has figured out a way to change the hardware in the last decade plus, there's no way to block a complete reflash except by software based lock of some kind..........

The programing interface/server is what controls this. It's not like the dealer holds the file for all Vipers in a folder like the early stuff. The programming tool typically looks to see what the vehicle/VIN is and what operating system or software version is loaded and then decides if there is an update available.
 
The programing interface/server is what controls this. It's not like the dealer holds the file for all Vipers in a folder like the early stuff. The programming tool typically looks to see what the vehicle/VIN is and what operating system or software version is loaded and then decides if there is an update available.

And that would make it software based.......maybe not the software on the laptop but software somewhere........hmmmmm, wonder where I heard THAT before??? :)
 
You both are correct. But the software is at corporate. At the dealership they have direct contact with AC since they are also a AC dealer. That enabled them to fix both issues quickly on the Cat and the Yamaha. Maybe Yamaha has the capability but I know Cat does.
 


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