SSM for OBD1 and OBD2 SVXs

[Huskymaniac]

There were bit of this on two different threads and I have an update so I figured I would just start a dedicated thread to make this easier for people to find later.

As mentioned previously, I bought two cables from the evoscan folks. One cable is a two-headed usb to both OBD1 and OBD2. This cable is meant to communicate only over the SSM pins using the SSM1 protocol. What we verified was that the OBD2 cars built from 1996-1998 use the SSM1 protocol, not SSM2. However, the memory addresses for the parameters were all different. I also bought an usb to OBD2 cable for my Tribeca which is supposed to be able to communicate over either the SSM pins or the OBD2 pins. I have not tested if it can use either SSM1 or SSM2 protocol or just SSM2 protocol over those SSM pins.

Thanks to information provided by Phil I have been able to determine most, if not all, of the memory addresses for communicating with OBD2 SVXs using SSM1. I have both the ECU and TCU addresses now and will eventually work on the climate control unit too.

On software, I have only played with my SVX so I can't say anything about how well any of them work on either newer OBD2, non-SVX, cars or OBD1, including SVX, cars. However, many people have played around with these packages for these cars and I assume the work fairly well. The gray area was with OBD2 cars from 1996-1998, including and especially SVXs.

The evoscan software is really nice BUT it can't communicate with the TCU or any other unit besides the ECU. What is can do is communicate using SSM1, SSM2 and OBD2. It has a variety of memory definitions for OBD1 and OBD2 cars and I have updated that file with the definitions for OBD2 SVXs.

JECScan is pretty bare bones and appears to be meant for communicating only with SSM1 protocol. BUT, it CAN communicate with the TCU and, hopefully, the climate control as well as other controllers. It looks like this software might be able to also communicate using SSM2 but I haven't tried it.

The released version of FreeSSM can only communicate using SSM2 so it only covers Subarus built after 1998. HOWEVER, I am working with the author to obtain a development version of the software that can communicate using SSM1. This is a major undertaking for me as I am not up on the new compilers and development servers. It may take some time to get a version of this working on OBD2 SVXs but the software appears to be better than JECScan and has the ability to talk to the TCU and possibly other controllers as well.

As far as the definitions for the memory addresses of the various parameters, here is what I believe is currently working for OBD2 SVXs:

ECU: Battery voltage, speed, RPMs, coolant temperature, ignition advance, MAF, TPS, engine load, injector pulse width left and right, idle control valve duty cycle, all three O2 sensor readings (average, max and min), air/fuel correction left and right, knock correction, atmospheric pressure and manifold relative pressure. I think I also have all three O2 heater signals too but I'm not entirely sure.

TCU: Battery voltage, both speed sensors, RPMs, ATF temperature, TPS, current gear, line pressure solenoid duty, torque converter lockup solenoid duty, center diff solenoid duty, MAF, TPS source voltage and two digital IO bytes that I haven't completely figured out yet.

I have the definition files for both the evoscan and JECScan software if anyone wants them. I hope to eventually have the definition files for FreeSSM too. And one other note about software is that these programs have other capabilities besides just reading ecu and/or tcu data. The evoscan program, with the appropriate cable, can flash some of the newer ECUs. It looks like JECScan can get a ROM dump. But all I really wanted was an SSM reader for my OBD2 car and it appears as though I am well on my way to that goal. And all you really need is a $57 cable and, maybe, a $20 software package and you can get an SSM reader for any SVX.

[pearlm30]

Thanks a lot for the update!

[jellybytes2]

Great info.. thank you.

[processengr]

Thanks Tony! Great news! I am ordering the cable this weekend.
I also have an "Ultraguage" to to test, will let you know what it reports when I plug it in to the 97. I already know that it cant read any TCU data.

[Huskymaniac]

Originally Posted by processengr

Thanks Tony! Great news! I am ordering the cable this weekend.
I also have an "Ultraguage" to to test, will let you know what it reports when I plug it in to the 97. I already know that it cant read any TCU data.

As I shake down the various software options, I am constantly revising the definitions files. Let me know when you get the cable and what software you want to try and I will send you what I have. Hopefully, by then, I will also have something for FreeSSM. I need to build what would effectively be the first TCU definition file for that software.

[Huskymaniac]

On a side note, has anyone been able to download and install the software from ECUTune? I extracted the files and tried to run the "click once" file but it said it was missing files.

[SoobCrazy]

Oh man, this is awesome! I never thought I would see the day when OBD2 SVXs were getting software love! You, Sir, are a gentleman and a scholar, and a fine judge of spirits, to be sure!

[processengr]

Originally Posted by SoobCrazy

Oh man, this is awesome! I never thought I would see the day when OBD2 SVXs were getting software love! You, Sir, are a gentleman and a scholar, and a fine judge of spirits, to be sure!

A big plus 1+!! I ordered the double headed cable!

[Coan]

Wow that's a lot to take in. Apparently I missed the previous threads on this.

What specific cable do we need to buy for this? I have a tactrix cable that I used for tuning my 2003 WRX, any chance that will work?

[icingdeath88]

Originally Posted by Coan

Wow that's a lot to take in. Apparently I missed the previous threads on this.

What specific cable do we need to buy for this? I have a tactrix cable that I used for tuning my 2003 WRX, any chance that will work?

Yea I am a bit confused as well. I need to make/get cables for me and steve herman, but I'm not entirely clear on what I need to get. I was thinking to make cables for LAN's ECUtuner software, since he and I both have OBD1 cars, however my 97 I don't think will work with that. Husky, any input? I am mid-move and kind of frazzled so I could use some guidance.

[Huskymaniac]

Originally Posted by icingdeath88

Yea I am a bit confused as well. I need to make/get cables for me and steve herman, but I'm not entirely clear on what I need to get. I was thinking to make cables for LAN's ECUtuner software, since he and I both have OBD1 cars, however my 97 I don't think will work with that. Husky, any input? I am mid-move and kind of frazzled so I could use some guidance.

The two-headed evoscan SSM1 cable will work with all SVXs, OBD1 or OBD2. I have made definition files for the OBD2 SVX for the evoscan and JECScan software. They both already have definitions for OBD1 SVXs.

[Huskymaniac]

Originally Posted by Coan

Wow that's a lot to take in. Apparently I missed the previous threads on this.

What specific cable do we need to buy for this? I have a tactrix cable that I used for tuning my 2003 WRX, any chance that will work?

I bought a similar cable for my Tribeca but haven't tried that cable on the OBD2 SVX yet. I'll try it and let you know.

[Huskymaniac]

More updates on this.

The OBD2/SSM2 cable does NOT work for getting SSM1 signals from OBD2 SVXs. The two-headed OBD1/OBD2/SSM1 to USB will work, and is what is needed, for ALL SVXs. One thing to note about the two-headed cable is that it does not connect to the OBD2 pins. It only connects to the SSM1 pins. I am not sure if diagnostic codes can be read and cleared via SSM1 yet. The cable I bought for my Tribeca might be able to communicate over the OBD2 pins but I haven't tried that yet. Until I dig deeper into the DTC stuff, I plan on using my OBD2 reader to read and clear codes.

On FreeSSM, I have finally been able to compile and run the development code and I wrote the definitions files for the ECU and TCU. It isn't working yet with my 1996 but I am working with the author of the code to work out the bugs.

Is there a way to post the evoscan and JECScan definition files on this site?

[icingdeath88]

Originally Posted by Huskymaniac

Is there a way to post the evoscan and JECScan definition files on this site?

Yes, you should be able to if they're not too big, otherwise, you can email them to me and I'll figure out a way to do it. Email address is my username @gmail.com.

[Huskymaniac]

Originally Posted by icingdeath88

Yes, you should be able to if they're not too big, otherwise, you can email them to me and I'll figure out a way to do it. Email address is my username @gmail.com.

When I try to "manage" my locker it just gives me the option to delete, not add.