Problem: v3.8 always in bootloader mode after startup

[PeepPaadam]

Customers VEMS unit developed a problem: after each startup VEMS is in bootloader mode, if you connect a laptop then VEMStune says that ECU is in bootloader mode (bad marker), if you choose leave, it will work just fine. Until you turn off the ignition.

Tried to flash the firmware, when it starts veryfing, after 12 or 13 pages it stops and displays message saying Firmware verification failed, firmware is different. I also tried to loopback the ECU and then flash firmware, no difference.

Please help.

[fphil]

You are probably aware of
Summary of operation/http://www.vems.hu/wiki/index.php?page=GenBoard%2FFirmware%2FBootLoader.
I may have also an issue with bootloader and V3.8.
I had errors at the ISP ports when I run the avrdude version 6.1 with my old ISPUSB cable. I had to use avrdude 5.10 (sync issue)

[PeepPaadam]

I already mentioned in the first post that I loopbacked the ECU but that did not made any difference.

[VEMS]

Hello Peep,

This indicates there has been some flash corruption on your ecu, was this a standard v3 assembled or some PnP application ? In case of PnP the likeliest cause is some flyback current back feeding into ground path. In any case most likely board processor will need replacing.

Best regards, Dave