keltik Posted November 14, 2008 Share Posted November 14, 2008 Hey guys, long time no post.. Im going to be fitting a speed cut controller to my VSS wires and would love a wiring diagram for the H6 ECU. If anyone can help me identify the VSS wires that would be great! Also i cant figure out how to get my Auto trans into FWD mode....doesnt seem to be a FWD fuse holder anywhere :-\ Finally i know you guys didnt get H6 Legacys before '03 but whats the approximate top speed of a H6 Outback? Our cars here are electronically limited to 185kph or about 115mph which is why im fitting the frequency modulator. I have a track day coming up at Pukekohe which has very long straights. Link to comment Share on other sites More sharing options...
keltik Posted November 16, 2008 Author Share Posted November 16, 2008 Nobody even wants to take a guess? Link to comment Share on other sites More sharing options...
nipper Posted November 16, 2008 Share Posted November 16, 2008 Its a weekend, it gets quiet. what in heck is a speed cut controller? 118 mph or thier abouts. Also you have two speed sensors. Also without one VSS you wont have AWD. If you cut out both you will be in limp mode and be speed limited to 50 mph. I really really dont think you need to do this or worry about it unless you have straightaways over a 1/2 mile long. You can make u[ for time on the corners as opposed to the straights. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 17, 2008 Author Share Posted November 17, 2008 (edited) Thanks for the concern nipper. Have heard from a few other Legacy and WRX drivers that they spend some time on the speed limiters at this track as it was primarily used for V8 Supercar racing. Was even hitting the speed limiter on the Taupo track in June and thats a lot more curvy! The speed cut controller acts like a frequency clamp and over speeds of 170kph it simply sends the same signal to the ecu as at 170 no matter how fast the incoming signal. So below 170kph everything operates as normal. It has 2 inputs and outputs for sensors so it caters for vehicles with 2 speed sensors. Still cant find a FWD fuse anywhere. Seems even the twin turbo versions of the same year have the fuse but mine doesnt. Edited November 17, 2008 by keltik Link to comment Share on other sites More sharing options...
nipper Posted November 17, 2008 Share Posted November 17, 2008 They phased out the the fuse as the TCU got more sophisticated. Your going to have to plug it in to both VSS. Otherwise the puter will think the wheels are spinning and can make for some wierd handling. If its just generating a signal, just wire it into the VSS wire. I dont think a sooby is going to like this, as you may not get the AWD working with you as it should. Someone must have a chip outhere that has taken off the speed limiter, or something like that. nipper Link to comment Share on other sites More sharing options...
nipper Posted November 17, 2008 Share Posted November 17, 2008 PS Now if you can half the pulse from the VSS sensors that may work for you. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 17, 2008 Author Share Posted November 17, 2008 Actually now that ya mention it a couple people in ClubSUB have made freqency divides that do exactly that. The only issue was the radiator fans stay on to a higher speed. Manufacturer claims this controller works with Legacys so ill give it a try when it arrives tomorrow. Just gotta get a wiring diagram Link to comment Share on other sites More sharing options...
nipper Posted November 17, 2008 Share Posted November 17, 2008 Ok here is some details. Vss1 vss2 and the torque converter turbine speed sensor all share the same hot. I am working off a 2000 manual, but there shouldnt be to much differnce. The They all have thier own feeds right to the TCU, so just get under the car and look at the wire colors, and hoepfully they will all flow the same. Use a meter. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 17, 2008 Author Share Posted November 17, 2008 Cheers mate, Is there just one speed signal going into the ECU or still 2? Also does the wire to the ECU come from the TCU or the sensors themselves? Newest manual ive got is for a '95 and of course everything changed since then Link to comment Share on other sites More sharing options...
nipper Posted November 17, 2008 Share Posted November 17, 2008 prvt me with your email. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 17, 2008 Author Share Posted November 17, 2008 Thanks mate Much better than the diagrams i was attempting to use Failure or success ill post up the results tomorrow night Link to comment Share on other sites More sharing options...
keltik Posted November 18, 2008 Author Share Posted November 18, 2008 Hmm...looks like although there are 2 speed sensors hooked up to the tcu - the ecu only gets one wire telling it the vehicles speed. So if anyone has a pinout for the H6 ECU or knows how i can figure out which one is the speed sensor that would be great. Link to comment Share on other sites More sharing options...
nipper Posted November 18, 2008 Share Posted November 18, 2008 Sheesh like i said, there is no ONE sensor doing the job. If one sensor fails, the ECU will use the second one to drive the spedo. You need both of them to make the AWD operate. The TCU compares front and rear output speed, along with other sources to determine how much RWD to apply to the car. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 18, 2008 Author Share Posted November 18, 2008 (edited) Im not saying your wrong mate but in all the documentation i can find it shows the ECU as only being connected to one speed sensor. And as the speed cut is activated by the ECU then its obvious that interrupting that one sensor is what i need to do. I may be wrong but im assuming the TCU will handle all of the AWD stuff and interrupting this sensor at the ECU end wont affect my AWD? The documentation for the controller also shows this for the EJ25 and EJ20 ECU and shows the pin to connect to, but it doesnt show the EZ30 ECU. Either way im willing to try it and see what happens under controlled conditions. If my idea doesnt work and sets off a million error codes then i can always remove the controller. On the other hand i do seem to remember there being error codes in the old ECU's for VSS1 and VSS2 failures..... Edited November 18, 2008 by keltik Link to comment Share on other sites More sharing options...
CNY_Dave Posted November 18, 2008 Share Posted November 18, 2008 Sheesh like i said, there is no ONE sensor doing the job. If one sensor fails, the ECU will use the second one to drive the spedo. You need both of them to make the AWD operate. The TCU compares front and rear output speed, along with other sources to determine how much RWD to apply to the car. nipper (kibbitzing without a schem in front of me) It does seem to make sense the ECU only needs one speed signal, while the TCU of course needs both. Dave Link to comment Share on other sites More sharing options...
nipper Posted November 18, 2008 Share Posted November 18, 2008 And the ECU gets the signal from the TCU. You can not spertae nor interupt that signal. You will afect engine performance, and may even throw yourself into limp mode. nipper Link to comment Share on other sites More sharing options...
keltik Posted November 19, 2008 Author Share Posted November 19, 2008 (edited) Just for future reference heres the results. All wiring diagrams show only ONE speed reading going into the ECU. If this reading is not as the ECU expects - the check engine light will illuminate and the vehicle will behave differently. Cutting this wire will not immediately trigger a CEL. The ECU must determine the signal is bad by evaluating other parameters and triggers a error code at around 80kph. However running a D-Check diagnostic will show that the sensor is not working. Adding the speed cut controller (GReddy and Pivot models tested) will allow the ECU to read the vehicle speed accurately up to a preset cut off speed. I set mine at 170kph. After the cut-off speed, the controller takes over and continues to tell the ECU that the vehicles speed is constant at 170kph. No CEL is triggered and the AWD does not seem to be affected. A Scantool did not read any new or stored error codes after my test runs. The Legacy successfully hit 215kph (according to GPS) on the test run with no hesitation or issues. The documentation for the controller states that BH, BC, BG and BF Legacys were supported and i doubt GReddy would make that statement without some degree of testing. *Disclaimer: This controller is a JDM only item and is not intended for road use. Test runs were not held on a public road. Nippers statements about speed sensors and AWD are correct, If the TCU doesnt get all of its speed readings correct (3 different sensors on my car) it will behave very strange and cause nasty handling issues. Edited November 19, 2008 by keltik Link to comment Share on other sites More sharing options...
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