JDM VL 4WS diagnosis

[Noriyasu]

A friend of mine is asking me for advice about a 4WS problem.
Very occasionally, the rear wheels seem to behave strangely.

He has requested that I add 4WS diagnostics capability to my SSM software.

However, there is very little information on 4WS, and according to Mr. Phil, it seems that the program of the 4WS ECU cannot be read from the SSM. The ECU and TCU can read the ROM code, so we were able to analyze it and identify the location of the trouble code.

I know what kind of trouble code there is from the maintenance manual, but I don't know which ECU memory it corresponds to.

http://www.alcyone.org.uk/ssm/4ws.html

However, I can't use this method for 4WS, you'll probably need to analyze the SSM-II ROM code to find out what it does.

That wasn't planned, but it looks like it will be a relatively large, high-priority project.

[Noriyasu]

The analysis of the 4WS controller is still in on the way, but I have some good news regarding the SSM cable, so I will write it here.

In addition to the SVX version, SSM for Windows also comes in an Impreza WRX version, but SF5 Forester users say they were able to access it with the EVO Scan cable.

Then, EVO scan cable may be useful for SVX '95 or later.

https://evoscan.com/product/subaru-s...baru-vehicles/

However, the '91-'92 models have a voltage problem with the SSM connector, which may cause instability, and the EVO Scan cable is not supposed to work with cruise control. However, it may be useful for getting other information.

[Noriyasu]

Today I did a '91-'92 SSM-II ROM code analysis to determine where the 4WD controller and A/C controller trouble codes are stored.

I will update SSM for Windows soon.

The new diagnostic function is expected to be useful for analyzing problems with the air conditioner and 4WS.

[Noriyasu]

Hello,

Today I added diagnostics for 4WS and air conditioning units to SSM for Windows, which should help you find miss connection or broken sensors.

https://grove-design-service.com/ssm/ssm_svx.html

I hope it will be helpful to you all.

P.S. To add this function, we created a tool to analyze the SSM-II ROM code. In other words, if I can get SSM-I/SSM-II cartridges, I will be able to diagnose old (non OBD2) SUBARUs that were not supported before. If you have an SSM cartridge that you no longer need, we would be very grateful if you could provide it to us. just ROM data is Okey and not need physical device.

[Noriyasu]

About SSM for Windows.

Since the reading of AC information parameters is unstable, I have decided to read them twice and verify them. it will be stable.

Please use updated 240805 version instead of 240804.

This summer in Japan is so hot, but almost of temperature parameters indicate too high. The temperature calculation formula is unknown, and it was previously adjusted in winter, so if it is not correct in summer, the coefficients are probably wrong.

Further analysis of SSM-II will be necessary to find the correct formula, which will likely take some time.

Anyway, if the sensor is connected correctly, the temperature value will change, so I think we can check connection of the sensor.

[Noriyasu]

Hi,

Today I updated the formula for the temperature parameters of the SSMW.

The AC controller temperature and ATF temperature will show the correct values now.

To get the formula, I needed to analyze the SSM-II ROM code, so I created a tool to do that.

The formula for A/C temperature was not a table, but a program. The ATF temperature sensor characteristic was non-linear and tabular.

Pls use 240810

https://grove-design-service.com/ssm/ssm_svx_en.html

[Noriyasu]

Originally Posted by Noriyasu

Hi,

Today I updated the formula for the temperature parameters of the SSMW.

The AC controller temperature and ATF temperature will show the correct values now.

To get the formula, I needed to analyze the SSM-II ROM code, so I created a tool to do that.

The formula for A/C temperature was not a table, but a program. The ATF temperature sensor characteristic was non-linear and tabular.

Pls use 240810

https://grove-design-service.com/ssm/ssm_svx_en.html

I fixed again. It should be Okey now. Use 240813.

[Noriyasu]

Analysis of SSM-II ROM is almost complete. I have obtained the correct calculation formulas for parameters other than temperature, such as O2 sensor voltage and motor current, so I have updated SSM for Windows. The latest version is 240818.

https://grove-design-service.com/ssm/SetupSSMSVX_240818

The formulas for calculating voltage, current, angles, etc. were unknown until now, but I think they are now almost correct. Many ECU parameters were 8-bit values, but in 4WS controllers, some angle values ​​are expressed as 16-bit values.

There may still be some mistakes, but I think SVX's SSM for Windows is almost complete.

I plan to update SSM for Windows for other SUBARUs as the future project. To start with, I bought an SSM cartridge for the Impreza on eBAY. If you have a Subaru that is not SVX before OBD-II and needs diagnosis, please request it. I may be able to help you.