Hello!
I have installed a vems into a car with modified oem harness. Grounding made like phatbob guide. The ecu seems fine, but after upgrade fw and config to 1.2.11 and calibrationg sensors and tps, burned changes and switched off. After turn on, lcd display work normally but no communication on serial port.
Then I tried to enter bootloder mode, it seemd fine, fw upload worked, but stay in bootloader mode. After turn off - on no communication again. Some trying with bootloader and fw upgrade show with old firmware (1.1.27) ecu works and communicates. With newer fw. like 1.1.96 stuck bootloader.
After that, I have tried install an another ecu into this car and loom. But it ded too. No communication just fw upload in bootloader mode.
I have checked the wiring, it seems ok, but I have no ide what happened. I dont want to destroy more ecu. Please help, what is wrong.
Thx