jrettenmayer Posted December 27, 2009 Share Posted December 27, 2009 The EJ is in and running in my 86 GL wagon. When I did the harness, I ended up cutting out everything related to the engine, then splicing it all together instead of what seems to be the most popular way and just cutting out everything NOT needed...except that I forgot to cut out the stuff for the cooling fan. Was planning on just running some electric fans (and I may still do that, except that I have the EJ fans that fit the EJ radiator I'm using, and it all goes in so nicely....I'd like to keep my EJ fans if possible. They have three wires running to each - I just need one of them to function for now, as I don't have A/C. How do I power it? I located the connector I need for the larger fan - one black wire, one Yellow/Red, and one Green/Black. My diagrams show the latter two running to an "A/C Short Connector". Located it. It looks to me like it just ties the two wires together. Do I need this connector? I have the main fan relay, and I understand how to power that, I think. One side to the battery with a 20 amp fuse, the other side to the Yellow/Red wire on the fan. And on the low voltage side of the relay, one side to accessory power and the other side to the wire from Pin D17 on the ECU. Is this all correct? Does the ECU ground d17 and trip the relay to turn the fan on? Why three wires instead of two into the fan? And...how do I turn the Legacy fan into a pusher rather than a puller? Thanks in advance! Quote Link to comment Share on other sites More sharing options...
subiekid Posted December 28, 2009 Share Posted December 28, 2009 Its 3 wire because it's a 2 speed fan, one wire is low, one high, one ground. to reverse the fan you need to reverse the polarity and double check the blade direction (I don't remember what the ej fan looks like but you may be able to flip the fan blade over on the motor to make it push more air) Get yourself a battery, ground the black wire and play with the other two.. you will see what they do. Then reverse the polarity, hook the black to the positive and repeat. Quote Link to comment Share on other sites More sharing options...
jrettenmayer Posted December 28, 2009 Author Share Posted December 28, 2009 Huh...ok. I did that, fan didn't really do anything. Well, it tried to move once when I grounded the Black wire and touched the Green/Black to the positive battery terminal. However, I think the battery might be too weak to make the fan operate. That is helpful, thanks! Now...it's 2 speeds. Which speed do I use? And, do I need to make use of the "A/C Short Connector"? What does that thing do? Also on this subject: The EJ temp sensor has a white/green and a red/green wire coming off of it. The white/green wire is spliced to the old temp sensor wiring coming from the gauges that run up to my gauges. The red/green wire runs to the computer (a21) and in the legacy harness also ran to the gauges. My temp gauge appears to be functioning properly currently - why did the red/green wire also run to the gauge cluster in the Legacy? Is it some sort of idiot light perhaps? Quote Link to comment Share on other sites More sharing options...
subiekid Posted December 28, 2009 Share Posted December 28, 2009 The Ej ecu has the cooling fan output wire(I don't have my diagrams here to give you the pin and connector), I took the original EA fuel pump relay (it's unused with the EJ) and used that as my cooling fan relay (it's just a regular single throw relay, you could buy one as well if you want... just make sure the amperage draw isn't too much for the relay, I only have 1 fan). I would wire the fan/s on high if it were mine, but to each their own. This bypasses the a/c portion of the fan control system. Get on http://www.the12volt.com/ for information on wiring in relays. I don't have any of my diagrams where I'm at but I remember wondering about something like that when I made my harness... if it works.. don't fix it. I would hook it up to an old laptop with vrg3's scan tool (see legacycentral.org under the "electrical section") to be sure you have the proper coolant temp reading, Or hook up a DVOM to the cooling fan output wire and run the car at idle and make sure you get an output out of the wire (it should be a ground iirc). Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted December 28, 2009 Share Posted December 28, 2009 The AC short, or sub fan connector causes both fans to operate together on AC equipped cars. This is the desired operation. I am pretty sure that the fans are operating at high speed all the time. Here's the crazy AC wiring diagram for the fans http://main.experiencetherave.com/subaru_manual_scans/FSM_Scans/ACwiringdiag.jpg And the regular fan diagram http://main.experiencetherave.com/subaru_manual_scans/FSM_Scans/1992_legacy_radiator_fan_wiring_diagram.pdf Regarding the temp sensor. There are two temp sensors (at least on the 90-94 Legacies) The one-wire sensor goes to the dash gauge, while the two wire sensor goes to the ECU. Both wires of the two-wire sensor need to go back to the ECU. One wire is the 5v reference voltage, and the other is the signal coming back to the ECU. Quote Link to comment Share on other sites More sharing options...
jrettenmayer Posted December 28, 2009 Author Share Posted December 28, 2009 Ok... I eliminated the A/C - I think this isn't as hard as I'm making it out to be. I just want to know if I need to include the A/C short connector or not. I don't really see if it serves a purpose. The two wires back into the ECU are connected. Pin d17 on the ECU goes to the relay, yes? Thanks for your wisdom, guys. Quote Link to comment Share on other sites More sharing options...
Legacy777 Posted December 29, 2009 Share Posted December 29, 2009 I would include the connector so both fans operate together. Quote Link to comment Share on other sites More sharing options...
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