I am currently modifying my diagnostic software to work with an ALDL type interface. This will allow anyone with an OBD1 ECU and the ALDL connector (or OBD2 connector with pin 9 populated) to read the Suzuki serial diagnostic interface.

Among other data you will be able to read:

Vehicle Speed
RPM
Injector Pulse Width
Ignition Timing
Short term Fuel trim
Long Term Fuel trim
O2 sensor output

MPG can be displayed (by calculation) if there is enough interest.

It is possible to read codes but this appears to be complex and can easily be achieved with the paper clip method.
You will also be able to clear codes without disconnecting the battery. I have full address definitions for at least one 16V model and most of one 8V model. I can modify the code to cater for other models but you will need to do some datalogging.

Software will be free but you will need to buy or build an interface. Who is interested?

but you will need to buy or build an interface. Who is interested?

Depends on what the interface consists of and how to build it?

Google ALDL interface there is lots of info out there. It was used on GM vehicles and other vehicles like Lotus that used a GM ECU. You need something like this one:

http://cgi.ebay.com/ebaymotors/GM-ALDL-Cable-w-OBD1-USB-Version_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem199ead3960QQitemZ110036334944QQptZMotorsQ5fAutomotiveQ5fTools

The only currently available scan tool that will read the Suzuki interface is the Tech1 and that costs several thousand dollars. The ALDL interface is compatible with the Suzuki ECU but the message protocol and data rate are different.

Count me in.

I have been scouring the net for information on the non-OBDII Suzuki ECUs for the last few months and I have seen your name come up on so many forums, I've followed every thread, and read your webpages.

I've had the drawings for an ALDL to PC (RS232) cable on my desk for a couple of weeks, it'll take a while to source the parts since few of them are likely to be available locally (I'm down in Latin America), I'm also looking at cobbling together an ALDL to USB cable (basically an ALDL to RS232 to USB)

One question - some of the stuff I've read suggests that this will not work with certain laptops, something to do with the baud rates supported by the UART - will this still be a problem?

With regard the datalogging - I'm not certain who much I can do there, but if you can tell me what's needed I'm willing to give it a shot, I do have limited access to test equipment

The link below will take you to a page with an ALDL to PC (RS232 serial port) interface.  I'd guess no more than $5~10 worth of parts, maybe $20 if you have to get the ALDL or OBD2 connectors.

http://www.suzuki-forums.com/attachments/suzuki-sidekick-escudo-vitara-geo-tracker/7371d1241390627-aldl-connector-aldl-jtgh1.jpg

I've never had a problem with the baud rate. Very early PCs couldn't support non-standard data rates but the UART they used has long since been consigned to history. You can check it easily enough if you have a PC and a laptop or two PCs. Connect them together with a null-modem cable or USB to RS232 interface. Then use a serial programme to send data between them, I use RS232 Hex Com Tool for testing, you can enter any baud rate you want.
I can guide you through the datalogging, some stuff like TPS, Vehicle Speed and RPM is easy to spot. Injector pulse width starts off at a default value, increases as you accelerate and then drops straight back to the default when you throttle back and it goes into fuel cut off. Ignition timing is output in degrees and is easy to check with a timing light. I've only tested this with a few ECUs so I can't be sure how much the address mapping varies.

Frankly, much of this terminology is over my head, but it sure sounds like something I need to learn. Could this be used , possibly in the future, to rewrite certain aspects of the fuel injection programming? You know where I'm going with this don't you Rhinoman? Turbo fueling.

Rhinoman,

The cable is available on ebay at a steep price and you have or will have the software.
I'm definitely interested and I know a few other people too so keep us posted.

Bill S

I've not yet seen any pre OBD2 ECUs that are easily reprogrammed, none that can be done down the diagnostic link. Some of the later 8V ECUs have EPROM and it may be possible to modify others using a daughterboard with EEPROM fitted. I don't know which ECU you have, I have been looking at the early 16V but haven't yet managed to pull the code.
I would recommend a USB interface using the FTDI chip, that way you will not be going through the UART which remnmoves any possible problems with the baud rate.
The code that I am modifying was originally written to communicate with my own ECU design, I have used an interface to convert the protocol to the Suzuki protocol and have logged data succesfully, I just need to modify the software to work directly with the Suzuki protocol. I have helped a few other guys that have tried the protocol with an ALDL interface and it is working with an Escudo in Russia, a Tracker in the US, a Baleno in India and my own Vit here in the UK so it seems pretty universal.

You can follow progress here:

http://www.rhinopower.org/

Seem to be some broken links there...

One more question - depending on the market the vehicle was built for, the ECU may or may not use an O2 sensor and I assume if there is no O2 sensor then it always runs open loop - how does that affect things?

I've not seen an EFI without an O2 sensor, if there isn't one then the value at that address will be indeterminate. The ECU ID code will be used to define the address map.

There are lots of broken links, I've only just got that domain and I'm putting stuff up as and when. Ultimately I will move all the old stuff over but I'm restructuring the whole sit. Old site:

http://www.btinternet.com/~j_holland

Rhinoman

I've downloaded the latest version of Rhinoview and unzipped it - when I try to execute it I get a message saying "cannot open file snort.bmp." - I do not yet have my aldl cable, hopefully I'll have that tomorrow.

OK, I've not built it properly then, trouble is it always works on my machine because the compiler picks up the files from the work directory. I'll give it another go.

I've put the image files into a seperate folder. You'll have to download it again, unzip the folder and give it a go. let me know if you get any more problems:

rhinoman|removethispart|@rhinopower.org

OK - no more errors (so far), and I like the fact that you allow the use of the "high" com ports, as my ALDL/USB cable shows up as Com 6, now I just need to get back to the vehicle (I'm in Florida and the vehicle is back in Guyana), so in about two weeks I'll let you know.