Re:JB74 OBD2 connection

SZ Viewer A1 is using CAN, the numbers after it relate to the module ID it is connected to, not the standard.

I found this link which explains a bit more about the different standards....

www.csselectronics.com/screen/page/simpl...xplained/language/en

AZ Viewer uses either ISO 9141-2 / 14230-w (KWP2000) on pin 7 or CAN on Pins 6 & 14. SZ Viewer states the protocol as CAN/CAN-UDS, according to this article

www.quora.com/What-is-the-difference-bet...and-the-UDS-protocol

CAN-UDS is derived from ISO 14230-3 (KWP2000) and ISO 15765-3 (Diagnostic Communication over Controller Area Network (DoCAN). That makes sense as the older Jimnys were KWP2000.

Your OBD2 doesn't appear to have pin 7 wired, but pin 15 is wired using L-Line, this is probably why the KWP prototcols fail.

Just looking at Torque, it doesn't list ISO15765-3CAN, just the more standard ISO15765-4CAN, that is probably the reason why it fails. ISO15765-4CAN is now mandatory in the US, so it might be that the some Jimny's come with a different CAN version or still have the KWP2000 available as well.

The Autool list several ISO 15765 protocols but doesn't say which CAN standard they support, I am guessing it doesn't have ISO15765-3, so again this is probably why this fails.

Anton Malykh (SZ Viewer A1 author) would probably be able to help you know which protocol is running in your Jimny, he was very helpful to me last week, just email him. SZ Viewer A1 on my older Gen 3 doesn't have CAN and uses K-line (KWP2000), but I see that at the top or in the PC version.

I suspect that the other person you saw with an Autool working has different wiring or a different standard.

Thanks, this is getting quite a bit more complicated than I had originally imagined!

Anyone know of any suitable software that would be compatible with ISO15765-3CAN?

DrRobin wrote: Your OBD2 doesn't appear to have pin 7 wired, but pin 15 is wired using L-Line, this is probably why the KWP prototcols fail.

its actually very simple to open up the plug on the Autool X60 and move the pins about, any chance that would help?

I am not sure it would work pin 15 is described as L-Line and is apparently just used to wake up the ECU before pin 7 is used, see

www.gendan.co.uk/article_3.html

This is rather interesting since the article says pin 15 was only used on earlier cars and then for K-Line (pin 7) which your connector doesn't appear to have. As far as I can tell pin 15 is not used for CAN. I wonder if your socket is missing a cable by mistake, or deliberate for your market and that makes it CAN only? The ECU might be cable of K-Line on pin 7, it might only lack the cable.

Unfortunately I don't have a Gen4 so can't tell you if pin 7 is wired, but there are others on here would be able to have a look for you.

I agree with you, it is crazy, a standard that is not a standard, but I see this all the time in my job (I am an electronics design engineer, specialising in router design and data comms systems).

Just seen this

'Using KWP2000 on CAN with ISO 15765 Transport/Network layers is most common. Also using KWP2000 on CAN does not require the special wakeup functionality.'

from en.wikipedia.org/wiki/Keyword_Protocol_2000

So L-line (pin 15) is not used for wake up when using CAN, so either Suzuki wired it anyway or they missed off pin 7.

If we have any JB74 owners from italy on the forum, could you please post a photo of the back of your OB2 plug.

Actually, it might be interesting to see how a UK JB74 OBD2 plug is wired too, anyone willing?