Select monitor and `90s SUBARU cars page
For those who love 90's SUBARU cars
Select Monitor(WRX) | Select Monitor(SVX) | Cruise Control
Reproducing the functions of the SUBARU Select Monitor on a Windows PC

When my car has a problem and I take it to the dealer, the mechanic connects a machine and checks it. That's the Subaru Select Monitor. This device has been updated several over the years, and it seems that the type called SSM2 was compatible with Subaru vehicles until about 1998, before OBD II became available. As the car gets older, parts here and there start to wear out. Until the 1980s, cars had carburettors, which can be maintained only by mechanical disassembly, but since they changed to electronic fuel injection using a microprocessor, the car becomes useless when the ECU or sensors deteriorate or become damaged even if the mechanical parts in working order. In Japan now, it is no longer possible to pass the vehicle inspection if a warning indicator such as a check engine light.

This is a big problem for the '90s cars. You usually need diagnostic equipment such as a select monitor since sensor degradation cannot be seen just by looking at it. It is difficult for users to obtain this because it is not sold to the general public though SUBARU dealers and only auto repair shops can buy it. However, there seems to be someone in the UK who analysed this select monitor. Please refer to "Diagnostics and Datalogging for Subaru SVX" website with click here. My software was basically designed from the information in there. Many thanks to Phil Skuse for the information.

What this software can do

What "Select Monitor for Windows (Alcyone SVX edition)" can do are as follows



  • Read ROM ID of the ECU(Engine Control Unit) (Able to read ID's even your car is not SVX)
  • Read and clear the ECU trouble codes
  • Read of current values of internal parameter of ECU and real-time graph display (up to 4 items)
  • Display of fuel control and ignition timing map in the data read from ECU or downloaded ROM data
  • Read whole ROM/RAM data in the ECU
  • Read ROM ID of the TCU (Transmission Control Unit)
  • Read and clear the TCU trouble codes
  • Read of current values of internal parameter of TCU and real-time graph display (up to 4 items)
  • Read whole ROM/RAM data in the TCU
  • Read of current values of internal parameter of Air Conditioning Unit and real-time graph display (up to 4 items)
  • Read of current values of internal parameter of Cruise Control Unit and real-time graph display (up to 4 items)
  • Read whole RAM data in the Cruise Control Unit
  • Read of current values of internal parameter of 4WS Control Unit and real-time graph display (up to 4 items)

  • Note1:The 4WS feature is a only for JDM "Version L" grade of SVX. The SVX I own does not have 4WS. This function have confirmed my by Mr. Ishikawa. Spetial thanks to him.

    Note2:The communication speed of the serial interface is slow at about 2000bps. Only a few parameters can be read out per second. Specifying many parameters slows down the display update. Cruise control in particular is pretty slow at 250bps.

    Note3:It takes several hours to read the ROM data. If you try to read it without starting the engine, the battery will definitely go flat. Take sufficient precautions, such as charging the battery with a charger.

    Example 1 : Coolant temperture

     The water temperature is constantly rising and falling in the SVX.

    Example 2 : AT Lock up

     Lockup is effective at 4th gear and non-acceleration, 4WD duty seems to be changed all the time.

    Example 3 : Knock correction

     Knock correction value increases when throttle is opened.

    Example 4 : O2 sensor value

     The raw O2 sensor data fluctuates and is hard to see, but the Max/Min values are easy to see. When the throttle is opened, the Max value increases, and when idling, the Min value gradually decreases.

    Download and install

    Download the zip file from the link below and extract it to any folder on your PC. I am not using the registry. Configuration values are saved in the "select_monitor.ini" file in the application installation folder. The .ini file cannot be customized for other SUBARU cars.(Support for other car models may be available upon request.)

    SUBARU Select Monitor for Windows (Alcyone SVX edition)

    Build 240224 Right click to download Change ini file folder.
    Build 240212 Right click to download Installer available.
    Build 240204 Right click to download 4WS Information works now!!
    Build 230317 Right click to download
    Build 230309 Right click to download
    Build 230307 Right click to download
    Build 230301 Right click to download
    Build 230224 Right click to download

    See "How to Install" for Windows beinner.

    If you download the ROM data (bin) of the ECU from the link below, you can display the fuel and ignition timing map. It's safer than actually reading from the car. Put the downloaded file in the same folder as the software. You will be able to select it in the combobox of MAP tab.

    Link to ECU Rom Images (  (A separate window will open.)

    Meter Cluster Gadget

    I had a request to move an analog meter, so I made the gadget.I'm still in the process of making it, but I'm getting tired of it, so I'll release it here for now.

    Once connect the SSM cable, the meter will work. In debug mode you can manually move the meter. At the moment, the various settings can not be changed except for the background color.

    SVX Meter Cruster Gadget
    Build 230320 Right click to download

    About the USB-Serial cable

    The select monitor protocol except cruise control unit is 5V TTL level asynchronous serial communication (UART).A USB-to-serial conversion cable is required for this communication on a Windows PC. Only the cruise control unit seems to use synchronous serial communication using the SSM1 older protocol. For this reason, I modified the cable introduced in "Diagnostics and Datalogging for Subaru SVX" to allow for synchronous serial communication.You can download the schematic of this cable on this page, so you can create it yourself. (If there are many requests, I will consider selling it.
    Some models of SVX have a voltage output from the ECU that does not conform to the 5V TTL standard. It will not be able to read and write data properly without voltage level correction even if you connect a 5V TTL standard USB serial cable to it. It seems to be called the '92 problem because this phenomenon was seen in the '92 model of SVX when people first encountered this problem.

    I designed two types of cables for use with this software. One is an improved version of the one introduced on the UK site, and the other is a new and original design. UK cables are slightly susceptible to noise, and if the engine is running and noise is generated, communication may fail and retry, resulting in a drop in communication speed.
    A similar USB serial cable seems to be sold by a company that provides software called EvoScan. But, I'm not sure it uses FT232R or not. This software uses the FT232R's unique function for synchronous serial communication. Therefore, it will not work properly which similar cable which uses other conversion chip.
    Rev1.1 New version (Recommended) Download the schematic in PDF
    Rev1.2 Update based on UK version Download the schematic in PDF

    I have some parts in stock, so I might make a cable if requestedif you can't make it yourself, please contact us directly by email. Although it is unconfirmed, the EvoScan cable may be used if you donot need cruise control function and your car is after '94.

    About Disclaimer and Updating

    In order to avoid trouble, I describe the minimum description of the license.

    Software License
    1. Prohibition of commercial use
      Use of the software is for personal purposes only. No commercial use is permitted.
    2. Licence
      This software may not be sublicensed, transferred or sold without permission. Free to distribute, rent or lend, copy or translate.
    3. Attribution of rights
      All title and ownership of this software and any copies thereof remain with "Grove Design Service".
    4. Disclaimer of warranties and disclaimer
      1. This software is licensed as-is. "Grove Design Service" makes no warranties of any kind, express or implied, including warranties of merchantability and fitness for a particular purpose, with respect to the Software.
      2. I am not responsible for any damages (including but not limited to lost profits and other consequential or incidental damages) arising from the use or inability to use this software.
    5. Support and updates
      This software was created from information provided by external sources and information contained in service manuals. There may be errors in the information, and parts not described in the materials are created by guesswork. Please let me know when you use it and find something does not works correctly. I will fix the software once reported information is correct or suitable, but I cannot promise when to update the software. Please note that I may not be able to respond immediately.

    About donations and contacts

    It took me some effort and money to design this software and cable. I can't decide how much maintenance I should do for the release of this software, but I decided to make this software a donationware. The method of donation shall be an E-mail type Amazon gift or PayPal. Donation amount is arbitrary. Please donate any amount if you use it and find it valuable. Email: Please contact the same email address for bug reports and improvement requests.

    Click Icon to PayPal me

    I thought about posting a link to Amazon Gift, but it seems that it is judged as a spam site (fraudulent site). Sorry to trouble you, but please search for "Amazon Gift Cards (E-mail type)".

    アクセスカウンター アクセスカウンター