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GerryAttrick

OBD2 DIAGNOSTIC CABLE TO LAPTOP USB

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Can anyone point me to a RELIABLE OBD2 cable that will connect to a USB port on a laptop for use with (eg) Carsoft or similar software.

I have had the software running OK thru an RS232 port but most laptops nowadays come without RS232 - hence the need to connect to USB.

Some cables apparently work and others are useless. I think there is a crowd in the South Island who do one (I seem to remember something to do with Purple in the name). An overseas supplier would be fine too provided someone can confirm the cables work

At this stage I think the CPS on my E39 is "dodgy" and I have the ABS light coming up on my wifes E36 318ti so time for some investigation

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If you've already got the rs232 cable you may as well get an rs232 to usb cable, they're fairly cheap on trademe, and you already know it will work (assuming you don't get a faulty cable)

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If you've already got the rs232 cable you may as well get an rs232 to usb cable, they're fairly cheap on trademe, and you already know it will work (assuming you don't get a faulty cable)

My car scanner doesn't seem to work with the usb-rs232 cable on my laptop. It does work on a laptop that has built-in rs232 port. Here's a forum I started in trademe getting some suggestions. I haven't tried most of their suggestions. http://www.trademe.co.nz/Community/Message...s.aspx?id=88888

Hope you have some luck. I'm still trying to solve this out myself

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My car scanner doesn't seem to work with the usb-rs232 cable on my laptop. It does work on a laptop that has built-in rs232 port. Here's a forum I started in trademe getting some suggestions. I haven't tried most of their suggestions. http://www.trademe.co.nz/Community/Message...s.aspx?id=88888

Hope you have some luck. I'm still trying to solve this out myself

Thats the same problem I have. My neighbour had the same problem and I located a cable that worked form a guy in Akaroa but I've lost his address. We found out his problem was not selecting the correct USB port in the software so he sent the cable back.

I know some work and some don't hence my query.

I have been given an old touch screen PC that has an RS232 connection so I might just use that in the garage for diagnostics - just have to see if I can get the touch screen option to work. Should be easier to use until it dies under greasy fingers :rolleyes:

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The joys of technoligy... thats why we have to charge the labour rates that we do... try $50,000 worth of scanning gear & computers...plus updates, training etc. And then some tosser comes in and asks ..can you check my car for me I'm broke... someone else tries to fix it... and then they're back again.. wanting to know whats wrong... yeah right. I need to get a new sign made... had one at the old workshop... CHARITY MOTORS HAVE MOVED and the mechanic that lends his tools is on holiday for 6 months.

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The joys of technoligy... thats why we have to charge the labour rates that we do... try $50,000 worth of scanning gear & computers...plus updates, training etc. And then some tosser comes in and asks ..can you check my car for me I'm broke... someone else tries to fix it... and then they're back again.. wanting to know whats wrong... yeah right. I need to get a new sign made... had one at the old workshop... CHARITY MOTORS HAVE MOVED and the mechanic that lends his tools is on holiday for 6 months.

Dear Glenn and others,

I found out the new address for Charity Motors Ltd.

Here it is:

Charity Motors Limited - Address and Enquiries

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My car scanner doesn't seem to work with the usb-rs232 cable on my laptop. It does work on a laptop that has built-in rs232 port. Here's a forum I started in trademe getting some suggestions. I haven't tried most of their suggestions. http://www.trademe.co.nz/Community/Message...s.aspx?id=88888

Hope you have some luck. I'm still trying to solve this out myself

USB-RS232 adapters are notoriously unreliable and cause havoc with any specialised software that requires constant fdata flow and dows not use flow control eg like with ODBII interfaces

In my years of experience of dealing with ibus data communications, everytime the interface doesn't work and the customer is using a USB-RS232 adapter, it has always been the USB-RS232 adapter that was causing the problem.

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Most corporate class laptops & ofcourse older laptops have the RS232 socket as standard. I've had major issues with Point-of-Sale systems that require RS232 on newer cheaper motherboards & I can report that it's a waste of time!

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RS232 is a definition for serial communication on a 1:1 base. RS232 defines the interface layer, but not the application layer. RS232 ports can be either accessed directly by an application, or via a thin device driver in the operating system.

USB is a bus system which allows more than one peripheral to be connected to a host computer via one USB port. The standard not only describes the physical properties of the interface, but also the protocols to be used, due to complex USB protocol requirements, communication with USB ports on a computer is always performed via a device driver.

Accessing RS232 port via an USB port, requires a second device driver which emulates a RS232, but communicates via USB. Since USB is shared by several devices, there will be delays in communication due to the double device driver (RS232 working on top of complex USB driver adds creates extra overheads). These industrial applications expect a certain timing with RS232 communications, and the timeframe in which it is expected to perform can't be met hence the problems.

So serial-usb converter is out of the question, a serial-usb cable are also a type of adapter and since it still connects via the usb port to access serial, it's also out of the question. It will always be creating a virtual serial port.

Get a PCMCIA card or a port replicator which can be found for much cheaper for certain laptops.

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The joys of technoligy... thats why we have to charge the labour rates that we do... try $50,000 worth of scanning gear & computers...plus updates, training etc. And then some tosser comes in and asks ..can you check my car for me I'm broke... someone else tries to fix it... and then they're back again.. wanting to know whats wrong... yeah right. I need to get a new sign made... had one at the old workshop... CHARITY MOTORS HAVE MOVED and the mechanic that lends his tools is on holiday for 6 months.

I totally sympathise and I rarely try to fix anything major on either of my BMWs. However I can't always get to a dealer with my car and local "service" often leaves a lot to be desired. An example was when my E39 kept running the battery flat . After paying $800 for a new alternator it came down to a problem that was automagically turning on the a/c.

I found the problem and told the garage what to fix.

I also still harbour a sneaking suspicion that parts are often replaced when a little bit of black magic can resurrect the old one. Its nice to know what is a possible problem and if its minor fix it myself. Must admit that there was no fault code shown when the nylon window sliders broke on the 318ti :wacko: but Google and BMW forums helped there.

Next problem to sort is a dodgy CPS...according to the BMW dealers last fault check during service. I don't mind paying for the labour costs but I get a bit tetchy about the cost of parts when I see what they go for overseas.

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RS232 is a definition for serial communication on a 1:1 base. RS232 defines the interface layer, but not the application layer. RS232 ports can be either accessed directly by an application, or via a thin device driver in the operating system.

USB is a bus system which allows more than one peripheral to be connected to a host computer via one USB port. The standard not only describes the physical properties of the interface, but also the protocols to be used, due to complex USB protocol requirements, communication with USB ports on a computer is always performed via a device driver.

Accessing RS232 port via an USB port, requires a second device driver which emulates a RS232, but communicates via USB. Since USB is shared by several devices, there will be delays in communication due to the double device driver (RS232 working on top of complex USB driver adds creates extra overheads). These industrial applications expect a certain timing with RS232 communications, and the timeframe in which it is expected to perform can't be met hence the problems.

So serial-usb converter is out of the question, a serial-usb cable are also a type of adapter and since it still connects via the usb port to access serial, it's also out of the question. It will always be creating a virtual serial port.

Get a PCMCIA card or a port replicator which can be found for much cheaper for certain laptops.

You mean like this

http://www.dealextreme.com/details.dx/sku.5572

This seems to be a great price and I am going to order one and see how it goes

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