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[JamesV6CDX]

I have an ELM 327 with a USB lead

Trouble is, can't get it to work.

It's installed a "virtual" com port, Com5. The software can see port 5 and it's all configured on correct baud rate etc.

When you tell it to connect to the car - it sucesfully opens the com port, but then says "cannot detect interface".

Any ideas?  :-/

[JamesV6CDX]

Just to add, the car IS OBD2 compliant.

[Entwood]

When I tried the ELM327 I seem to remember a major "faff" changing/configuring ports until I found one that worked ....  one reason I changed to the Maxscan ..

[Jimbob]

using some bits like that, Ive had to force the virtual port to be port 1, then worked ok.

[JamesV6CDX]

using some bits like that, Ive had to force the virtual port to be port 1, then worked ok.

I will play in more depth tonight.

Essentially then - disable com1 in the bios, and try again? 

[JamesV6CDX]

Thing is - the lead remains red when plugged into the car - does this indicate for whatever reason, it's not getting any power from the ODB2 socket?

[Jimbob]

what currently has com1?
My bet is nothing.

shouldnt need to go to bios level, unless it was to disable the existing serial port 'com1' in which case you wouldnt be using an adapter in the 1st place.

device manager and the ports section should be all you need.

if something like a modem has com1....redirect that furher down the list.

[Kevin Wood]

If you open that COM port with (e.g.) Hyperterminal you should get an AT-command style interface similar to a modem (remember them?).

Set the right BAUD rate and see of you can ping it with AT and get an OK response back. This will prove that the USB interface is OK and the ELM chip is working.

Some adaptors power the USB to serial chip from the USB port but the ELM chip is powered from the Diag socket so it won't be recognised unless plugged into a car.

ELM327 chips can default to one of 2 BAUD rates depending on how they are bootstrapped. (9600 BAUD or 38400 BAUD IIRC.) Worth trying both of those.

Kevin

[JamesV6CDX]

The laptop has a physical  9pin serial port , shock horror

[Jimbob]

The laptop has a physical  9pin serial port , shock horror

use it then! and file the adaptor away 

[TheBoy]

Most of the freebie apps need it to be on Com1-com4.

COM4 rarely conflicts on any laptop, so thats a good start

[TheBoy]

Most lappies:

COM1 - 9 pin serial (if it exists - beware it may exist in chipset, but no connector!)
COM2 - Infrared
COM3 - Modem
COM4 - free

[Kevin Wood]

The laptop has a physical  9pin serial port , shock horror

use it then! and file the adaptor away 

I'm guessing the ELM lead has a built in USB-to-serial chip. Mine has (but it works flawlessly)  :-/

Kevin

[TheBoy]

The laptop has a physical  9pin serial port , shock horror

use it then! and file the adaptor away 

I'm guessing the ELM lead has a built in USB-to-serial chip. Mine has (but it works flawlessly)  :-/

Kevin

Believe they do.  The one in my kitchen that doesn't belong to me has usb to serial built on the board

[JamesV6CDX]

mine only has a USB end on it