Hi
I'm new to the forums, and not really sure if this thread is in the right place. Hope the moderators can move it if there is a subforum better suited
My problem: vemstune can't communicate with the ecu
v3.6 assembled from vems.hu, new twinshield harness from vems.hu. Checked the wiring, tx, rx and ground go to the right places.
What I've tried so far: windows 10, windows 7, windows xp, ftdi chipset usb-adapter (from vems.hu), three profilic usb-adapters (three different chips), different versions of the drivers to the usb-adapters, different versions of vemstune.
the (long) story: v3.6 controller and twinshield harness bought in 2014 used to control a Volvo b21 engine in a Volvo 940, and worked like a charm even with a profilic usb-rs232 adapter. Car was damaged by fire in the interior and scrapped, but the vems-ecu and engine survived and was stored a year in my garage before I acuired a volvo 740 to put it in. I bought a new harness (wasn't able to salvage the old harness due to molten plastic from the interior all over the wires) and mounted everything exactly as it was in the 940. The engine fires right up and drives just like it did when in the 940, but I've not been able to get vemstune to detect the ecu.
I'm now wondering if something inside the ecu (related to the rs232 communication) has been damaged, and how and what to check. I've looked inside the ecu and can't see anything obvious. My laptop was connected to the ecu when the fire was put out with water, so perhaps something shorted and damaged the rs232 circuit inside the ecu?
I know all the usb-adapters I've used work like they should by looping pin 2&3 in the adapters and typing stuff in a terminal-program. I've also tried to send "S" to the vems-ecu (as per this
thread/post) but get no response. I've also tried looping pin2&3 on the vems side to force the ecu into bootloader mode, but nothing happens.
Any suggestions?
