Guest |693| Posted July 13, 2011 Report Share Posted July 13, 2011 Hi! Mazda RX7 1998 w Vipec PnP Vipec ECU will not see DI1(aircon request) when switched on. AirCon works w stock ECU. Voltage @ DI1, pin 4V(measured between gnd & pin 4V) is 1.2V w AC switched on. This is due to AC request beeing fed through blower motor resistor and a diode(0.4V over resistor & 0.6V over diode). If I bypass the diode Vipec will recognize the signal(0.4V) but 1.2V is to high. How do I solve this? Regards Marco Quote Link to comment Share on other sites More sharing options...
ashesman Posted July 14, 2011 Report Share Posted July 14, 2011 This problem is resolved on some of our other plug in ECUs by placing diodes in series with a resistor to lower the DI voltage. Each diode will drop around 0.6V. Your ECU already has the resistor on the bottom board, so only a diode needs to be added. If you put one diode in the wire to pin 4V the problem should be resolved. Put the stripe end of the diode towards the ECU. Pretty much any standard diode will do (eg 1N4148 or 1N4007). [attachment=0]AC on DI.JPG[/attachment] Quote Link to comment Share on other sites More sharing options...
Guest |693| Posted July 14, 2011 Report Share Posted July 14, 2011 Hi! In the picture 2 diodes are installed? Is this correct? Tried installing one diode and it helped a little bit, with fan in pos one Vipec D1 will recognize AC on but @ higher fan levels the voltage @ pin 4V goes over 1v and DI1 shuts off. Marco Quote Link to comment Share on other sites More sharing options...
Guest |693| Posted July 14, 2011 Report Share Posted July 14, 2011 More questions........ When AC button is off voltage @ 4V is approx battery voltage. When AC button is on voltage @ 4V is approx 0.6V w diode connected. When AC pressure switch(in series w AC button) is open due to high pressure, voltage @ pin 4V is 0v=gnd. This means that Vipec ECU does not understand that AC systempressure is to high and just keeps running the AC compressor. How is this supposed to work? All i now is that w stock ECU AC button works and AC compressor starts/stops depending on system pressure(pressure switch) Marco Quote Link to comment Share on other sites More sharing options...
Simon Posted July 15, 2011 Report Share Posted July 15, 2011 Hi Marco We did strike this on early production boards. Can you check the board you have has a couple of wire links on the bottom side. If you do we will have to do some more investigating. I would also suggest avoiding use of the AC in its current state as if left on the system will over pressurise and blow a hose. Quote Link to comment Share on other sites More sharing options...
Guest |693| Posted July 15, 2011 Report Share Posted July 15, 2011 Board looks like this. Can you send me a functional board today? Have already spent 15hours to work out these AC issues which i probably will have a hard time getting paid for Regards Marco Quote Link to comment Share on other sites More sharing options...
Simon Posted July 17, 2011 Report Share Posted July 17, 2011 Hi Marco The board you have is current. The catch is that even a replacement board will have the same problems. Do you by chance have a pin out for this car or know all the AC pins and their function. Quote Link to comment Share on other sites More sharing options...
Guest |693| Posted July 18, 2011 Report Share Posted July 18, 2011 I have a PDF wiring diagram for the car. Regards Marco Quote Link to comment Share on other sites More sharing options...
Simon Posted July 19, 2011 Report Share Posted July 19, 2011 If you could email the PDF would be great. [email protected] We might be able to find a fix from this. Quote Link to comment Share on other sites More sharing options...
Guest |693| Posted July 19, 2011 Report Share Posted July 19, 2011 Let me know if the file went through, 32MB..... /M Quote Link to comment Share on other sites More sharing options...
Simon Posted July 26, 2011 Report Share Posted July 26, 2011 Got the file now have some working out to do. Quote Link to comment Share on other sites More sharing options...
Evil_Rotary7 Posted February 13, 2019 Report Share Posted February 13, 2019 Was this problem solved at the end? I am having the exact issue with Link G4+ plug ins on my FD. "When AC pressure switch(in series w AC button) is open due to high pressure, voltage @ pin 4V is 0v=gnd. This means that Vipec ECU does not understand that AC systempressure is to high and just keeps running the AC compressor. " Once the AC pressure switch 'clicks', I no longer able to turn off AC compressor, it will stay on. It's like the pressure switch is working the opposite way as it suppose to be. Takshit 1 Quote Link to comment Share on other sites More sharing options...
MaxRidell Posted June 20, 2019 Report Share Posted June 20, 2019 Is this problem resolved some how? I bought the car 5 years ago and the ac still doesnt work. Do you have a guide? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.