Eldiarslet Posted April 29, 2023 Report Share Posted April 29, 2023 Hello Ever since i got a link g4+ installed by a tuner in my sti my ac has not been working. Found out that it was because the ecu was switched since the ac kicked in when given a direct power supply. Today i managed to connect to my ecu for the first time and did some digging around and i don't get a single response from either ac request or ac clutch when pressing the ac button. So my first question is since the ecu is plug and play should it recognize the ac button signal or does that need to be connected somehow when installing and my 2nd question is if it should be recognized by the ecu what would make it not be? Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 29, 2023 Report Share Posted April 29, 2023 What ecu and what car/chassis/engine? Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted April 30, 2023 Author Report Share Posted April 30, 2023 5 hours ago, Adamw said: What ecu and what car/chassis/engine? Link g4+ Pnp in a Subaru sti 2006 ej257 Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 30, 2023 Report Share Posted April 30, 2023 5 hours ago, Eldiarslet said: Link g4+ Pnp Can you be more specific please. A 2006 could have a WRX9+, WRX104+ or WRX107+ ecu. Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted April 30, 2023 Author Report Share Posted April 30, 2023 (edited) 9 hours ago, Adamw said: Can you be more specific please. A 2006 could have a WRX9+, WRX104+ or WRX107+ ecu. It's a wrx 107+ So when I'm in the ecu Ac request is on digital input 3 and Ac clutch is on Ai 6 but when I checked if the ac button made anything turn green it didn't. I also tried to turn ac request and ac clutch on manually through the link software but the ac didn't turn on at all. I'm hoping it's just a matter of telling the ecu which pins the ac is connected to or something along that line. I'm completely new to playing around with my link ecu since my engine builder and a tuner have done everything so far Edited April 30, 2023 by Eldiarslet Wanted to give more information in my post Quote Link to comment Share on other sites More sharing options...
Adamw Posted April 30, 2023 Report Share Posted April 30, 2023 So if you go to Ign drive 6 and change its function to "Test (ON)" when the engine is running, the AC clutch doesnt engage? Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted May 1, 2023 Author Report Share Posted May 1, 2023 19 hours ago, Adamw said: So if you go to Ign drive 6 and change its function to "Test (ON)" when the engine is running, the AC clutch doesnt engage? No the clutch didn't engage but i could hear a relay click when doing that. I also tried to change the pullup resistor to on on Ac request and took a video (https://imgur.com/a/Lkc2Kr7) when ac clutch turned green this time i didn't hear the relay click but when ai 7 engine fan 1 turned green the engine fan actually turned on Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 1, 2023 Report Share Posted May 1, 2023 It sounds like possibly the pressure switch is open. Does yours have the manual AC system like this: Or the Auto AC like this: Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted May 2, 2023 Author Report Share Posted May 2, 2023 8 hours ago, Adamw said: It sounds like possibly the pressure switch is open. Does yours have the manual AC system like this: Or the Auto AC like this: Auto ac Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted May 2, 2023 Author Report Share Posted May 2, 2023 Im also curious why the ac button doesn't trigger di3 ac request. If I get the ac to trigger there is no point if i have to do it in the link software and not with the ac button Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 2, 2023 Report Share Posted May 2, 2023 If the pressure switch is open neither the AC request or the AC clutch will work, they are both supplied 12V via the press switch. I would start by unplugging the press switch and bridge the two wires together with a paperclip or similar to see if you then get an ac request. Quote Link to comment Share on other sites More sharing options...
Eldiarslet Posted May 19, 2023 Author Report Share Posted May 19, 2023 On 5/2/2023 at 3:44 PM, Adamw said: If the pressure switch is open neither the AC request or the AC clutch will work, they are both supplied 12V via the press switch. I would start by unplugging the press switch and bridge the two wires together with a paperclip or similar to see if you then get an ac request. Hello again, just wanted to say that i finally got some answers today to this problem. I measured the voltage from the cables going to the pressure sensor and got a couple of volts difference when the ac button was on and off. I then tried to jump the cables as you suggested and low and behold now the button could trigger ac request and ac clutch and the clutch actually turned. It's funny because i had my local Subaru workshop look at the ac a while back and they said it didn't connect from the ecu to the compressor. 2 weeks ago it was at their place again and i wanted them to fill the system but the mechanic misunderstood the work order and said when I picked it up that it still didn't connect from ecu to compressor but he vacuum tested it and it didn't leak but it was empty. Can't believe they didn't know the ac doesn't trigger when there is no pressure at the pressure switch. They will fill the system next week and if it doesn't trigger then i guess the pressure sensor is bad, looks like I'll be enjoying ac this summer which is nice since it's said to be one hot summer here in Sweden Quote Link to comment Share on other sites More sharing options...
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