OBDII Signal Splitter (for Infiniti G35)

Caelric · 01-29-2006, 02:21 PM

Well. I have a dilemma. There is a VERY nice OBDII interface and computer protocol, along with a hardware solution, specifically built to interpret the signal from a late model Infiniti and/or Nissan, designed for the G35 and the 350 Z; you can read about it HERE

However, I currently have this, a nice looking, stand alone multi function OBDII reader/gauge. the Blitz R-Vit. It certainly doesn't do half the things a carPC with the above referenced software could do, but I really like the simple interface and easy to read gauges.

I would like to keep the Blitz gauge I have now, but also have some sort of OBDII reading software on my carPC, probably the one referenced above. However, they both interface with the OBDII port; so, the question I have, does anyone know of some sort of dual port OBDII plug, or a signal splitter, or even something as simple as a KVM switch type solution, so I could have both plugged in at once, even though I could only have one actually interface with the OBDII at any one time, but I could switch between them by flipping a switch?

Thanks for any help
Dave

joeyoravec · 01-29-2006, 07:34 PM

When I program my own software I use a dual-J1962 breakout box and configure the two interfaces for different addresses. There's nothing fancy required, you can connect several interfaces to the network at one time with different addresses. Will your CarPC software offer this flexibility?

Unfortunately your two tools may be hardcoded to use the default tester address. In that case you would need a switch-box so they won't conflict by trying to answer on the same address at the same time. I've never seen a switch-box for sale; you may need to hack something together. You could build something completely custom with connectors from obd2cables.com. Another option is to modify a dual-J1962 box with a switch/relay on the network or power lines so only one tool is active at a time.

Caelric · 01-29-2006, 08:46 PM

Thats the answer I was looking for, thanks!

Dave

Lukeyson · 03-28-2007, 05:05 PM

It looks like obd2cables.com have a few options now too.

Like this 1x1962M->2x1962F Y splitter: OBD2Cables.com

Or this passthrough style header - although you'd have to wire up the 2nd end (With another J1692 or a DB9 for a scantool) OBD2Cables.com

Joey (if you're still around) you answered an 11bit CAN question of mine elsewhere. With regard to 'plugging in a factory OBD tool' and 'using a generic tool to sniff the activity' - I'd simply need to just listen to the traffic and filter based on the functional/physical address 3df-3ef right?

If I understand you right and there's no concept of real physical addressing in 11-bit CAN, then the requirement to 'change the Scantool address' as you list above would appear to exclude 11 bit CAN.

Have I got that right? Or is there more to it that I'm missing?

Luke Plaizier

Caelric · 03-28-2007, 06:45 PM

Wow, blast from the past!

Thanks, though, that is exactly what I am looking for. Too bad they are out of stock, but I will get one when they are in stock and try it out.

Dave

Lukeyson · 03-28-2007, 10:37 PM

I thought I'd post here that my question was answered in this thread: http://www.mp3car.com/vbulletin/obd-...sing-help.html

thanks Joey

Caelric · 04-06-2007, 06:39 PM

Well, I got the signal splitter from OBD2Cables, and sure enough, as I had thought, but was not sure, if there are two devices connected to it, you get errors on one of the devices. Oh well.

Brock · 04-14-2007, 09:31 AM

Quote: Originally Posted by Caelric

Well, I got the signal splitter from OBD2Cables, and sure enough, as I had thought, but was not sure, if there are two devices connected to it, you get errors on one of the devices. Oh well.

Your G35 uses the ISO9141 protocol/interface, which is not commonly used
as a network bus. You will have to switch between each scan tool. Should be
easy to modify the splitter cable that you have though with some sort of switch.

Caelric · 04-14-2007, 11:24 AM

Yeah, I wish it were that easy; I'd like a KVM type switch thing, but while I'm pretty good with wiring (I did my entire carPC and audio install myself), making a switch is a bit beyond me.

Brock · 04-14-2007, 08:32 PM

Quote: Originally Posted by Caelric

Yeah, I wish it were that easy; I'd like a KVM type switch thing, but while I'm pretty good with wiring (I did my entire carPC and audio install myself), making a switch is a bit beyond me.

You only need to switch one wire... the K-Line. In total, your interface needs 3
pins, power (pin 16), ground (pin 4) and K-Line (pin 7). Your 2 scan tools are
both for powertrain diagnostics, so only the K-Line is doing the communication.