Since I'm so tight that I squeak when I walk, I thought I would share some cheap ways to make your own OBD-II cable for use with OBDII scan software and hopefully MTH (My primary reason for making it).

I'll post my results within a week or two when I solder it all together, but if it works... no more spending $100+ on $30 worth of parts.


http://www.planetfall.com/%7Ejeff/obdii/

Thats the link to the schematics, and parts needed.

 

Hmmm, that is VERY interesting. Too bad I already bought my cable - or I would have tried it. For anyone with basic electronic skills, it looks easy to make. Alot of folks might not have the skills to tackle it. Good luck with it!

 

More useful would be a schematic for a USB cable. The days of serial are are gone.

 

USB is alot more difficult seeing as you'd need a USB->Serial controller chip and driver software.

The OBDII port is natively a 9600 baud serial connection, for which classic style serial ports are the perfect solution.

 

That's my point - laptops haven't been made with a serial port in 4+ years.

 

They just need to make ODB-3 a USB2.0 compatible connector, and flashing/detecting would be a ton faster (near instantaneously compared to 6+ minutes for a 60k file)

 

That certainly would be ideal!

 

Then it's a good think my circa 1998 Vaio laptop is still happy. Wish it had more than 1 usb port though.

 

http://www.mouser.com/index.cfm?hand..._pcodeid=62602

That would handle the USB -> RS232, plug that straight into the 'magic box'. Or if you were really skilled they sell a USB->UART IC for 5.70

Parts list from Mouser.com:

Part #Mfr.'s
Part #Manufacturer
Description
Your Part #Order
Qty.PriceExt.551-PS2501-1 PS2501-1NEC/CEL
DIP-4 Hi-Iso Photo 1-Ch
2501-3 IS 3 OF THESE 3 $0.24 $0.72 511-2N3904 2N3904STMicroelectronics
TO-92 NPN General Purpose
T1 & T2 2 $0.32 $0.64 833-1N4004 1N4004-TMCC
DO-41 Vr/400V Io/1A BULK
D1 & D2 2 $0.05 $0.10 291-1K 291-1KXicon
1/4WATT 1KOHMS 5%
R1,R2,R5,R6,R7,R9 10 $0.07 $0.70 291-1.5K 291-1.5KXicon
1/4WATT 1.5KOHMS 5%
R3 10 $0.07 $0.70 291-10K 291-10KXicon
1/4WATT 10KOHMS 5%
R4 10 $0.07 $0.70 291-150K 291-150KXicon
1/4WATT 150KOHMS 5%
R8 10 $0.07 $0.70 647-USR1H010MDA USR1H010MDANichicon
50V 1uF 4x7
C1 1 $0.21 $0.21 571-7478404 747840-4AMP
PLUG FRNT MTL SHL 9P
DB9-M 1 $1.15 $1.15 571-7478444 747844-4AMP
RECP FRNT MTL SHL 9P
DB9-F 1 $1.36 $1.36 501-FR4X6S 501-FR4X6S
4X6 FR4 COPPER PCB
2 $1.96 $3.92 Sub Total: $10.90

Only other thing you need is etchant, such as Ferric Chloride, a RS232 cable (I had one laying around) and the OBD2->DB9 Connector (AutoTap replacement cable $19.99 works).

 

http://cgi.ebay.com/ebaymotors/ws/eB...category=43989

I'm pretty sure that would work too (it costs as much as it costs to make one by hand heh). Shame I didnt see that earlier!

 

be carefull buying an OBDII connector with the elm based chip inside as it wont work with some cars and wont work with MTH trust me i know

 

The ELM setup seems like it should work, any definite reason that it didnt?

 

i dont have any definate reason why but the Elm chip wont work with MTH and only with some brands of cars

 

The reason I ask is because they show that their OBD-II Cable and software works with Mini Cooper 02+

 

yeah dont get me wrong i bought a OBDII cable with the elm chip

the software available for this setup is very basic and as i said it wont work with the MTH software
but you can read some codes from some of the modules on the car
but if you want to do this properly wait for Bim com to be released
now that will be serious diagnostic software

 

OK, i got the obd2 thing to work with the free software, the problem is, my neighbor backed over it before i could try MTH

 

i am getting confused about this cable issue. i think its just me tho. i have a sensolutions mono-com cable for my MTH software and thats working fine.
I then wanted to get the Auterra Dyno-Scan software but noticed that its $239 for software and their cable or $99 for just the software... i have a cable so does that mean i can just get the software alone. I emailed them and told them what i had and they just told me i need to buy the whole package, is this true or are they just trying to make more $ off of me? is an obdII cable just an obdII cable or is theirs special and different?

http://www.auterraweb.com/index.html

 

most obdII manufacturers build in a dongle into their cables so their software will only work with their cable,
I bought a generic cable and none of the software I downloaded worked with it.

 

is there any way around that?

 

not that I found,
unless you can decompile and remove the software interlocks in the programmes,
if you do let us know

 

a little tricker to work with than ferric choloride, but much more green for the environment. Althought it won't clear your plumming pipes :smile:

 

So im seeing that theres a chance there are certains cables out there that wont work with the MTH system?

I use a OBDII-USB cable to d/l my Dinan software which i was going to use with the MTH files but im now worried it will not work after reading all these posts.

 

Give you guys a chance and you all can make a mountain out of a mole hill. This thread is about as clear as flight path to the moon

When I asked Volker what cable to get this is what he said:

"MONO USB is the one."
Whatever the heck you have written above makes no sense and in this particular case looking for the cheap way out will wind up being the most costly in the end.

And you can get it from:

http://www.sensolutions.com/product....php?category=1

 

I use a Unitronic OBDI-OBDII adapter with Dinan seriel port connector ( OBD-USB ) to do software flashs here.....Im just concerned that its there own set up and it wont work like everyone is stating with other cables. My best bet is to try uploading it onto Cartunes and see if it works i guess.