Flyerborn Posted October 5, 2018 Share Posted October 5, 2018 Hey everybody! I've tried to do my due diligence to track down this little wiring gremlin I've been dealing with, but I think I'm finally to the point of requiring help as my searches have led me to a dead end. Got this car for $200 and have been slowly going through it bit by bit and I think the final issue I'm running into is that the electric fans don't work. The A/C fan is shot entirely so no surprise why that one doesn't turn on, but wiring up the passenger side shrouded fan to 12v shows that the fan will indeed run, my issue is that I've got no power to the positive terminal of the fan connector next to the radiator. (somebody has obviously run into this issue before because whoever the previous owner was ran a toggle switch to a permanent 12v.) Possibly explains why it's needed a headgasket before too, but I digress.... I'm trying to track down where the voltage is being lost as from what I can tell in the wiring diagram of my Haynes manual, the fan receives power from the battery, through a fusible link on the passenger strut tower, and then through a 'headlight relay' directly to the fan motor, which then grounds through the radiator via a thermo switch. Is that correct? From my interpretation of this shoddy diagram, it looks like the fan should have constant voltage with the ignition turned on, and I have voltage on both sides of the fusible link, but I do now know which relay is the headlight relay. I do know that the headlights work without issue, but I suppose it could always be a double pole relay and one side is not working properly. If anybody can tell me which relay to look for and which wires to trace or other components that could be causing this, it would be greatly appreciated! Thanks guys! Quote Link to comment Share on other sites More sharing options...
DaveT Posted October 5, 2018 Share Posted October 5, 2018 Model and year would help. If you can, try to find a Subaru factory service manual. You might find scans online / on forum. Or sometimes actual books on ebay. They are much more detailed and worth it if you intend to keep the car. Quote Link to comment Share on other sites More sharing options...
Flyerborn Posted October 5, 2018 Author Share Posted October 5, 2018 Whoops! Completely forgot to put year, and model. It's a 1982 GL Wagon. It's really in pretty terrible shape but the engine fired right up once I got the fuel pump working. I've looked around a little for a factory service manual, but haven't had too much luck. I'll keep looking the interwebs for them though. Couldn't be that difficult, right? For now, this is the Wiring diagram I've been trying to work from.... Quote Link to comment Share on other sites More sharing options...
George1943 Posted October 5, 2018 Share Posted October 5, 2018 Easy. Just look in the same forum where you posted your question. On Sept. 25, Eric Anderson has a link to a 1982 Subaru FSM. He spent a lot of time scanning it and posted it for all to share. I, for one, really appreciate the trouble he went to to do that for us. . . Quote Link to comment Share on other sites More sharing options...
naru2 Posted October 6, 2018 Share Posted October 6, 2018 Fan should have 12 volts via fuse #4 anytime key is on. Probably a blue wire. Check the harness connector. Quote Link to comment Share on other sites More sharing options...
skishop69 Posted October 6, 2018 Share Posted October 6, 2018 Fan has power (+ voltage) when the key is on and is turned on by the temp switch in the radiator grounding the circuit. Quote Link to comment Share on other sites More sharing options...
Flyerborn Posted October 6, 2018 Author Share Posted October 6, 2018 The operation of the system seems very rudimentary for the most part. I'm just having the worst time tracking down where my voltage is dropping out. As far as I've diagnosed, all of my fuses and fusible links are in good working order which I guess leaves only the headlight relay the missing link I suppose, but the spaghetti of wires on the passenger side fender/bay makes it very difficult for me to physically trace wires to where they're supposed to go. Does any of the fan's wiring go directly through the firewall at any point during it's circuit? And if not, which relay is the headlight relay? My only other knowledge is that the headlights turn on without issue which I suppose would mark it off of the list of things I need to check, unless I'm missing something entirely? George - Thank you for the heads up! I did find and download the service manual that it on that post. I will scour through it to locate a better wiring diagram. Thanks! 1 Quote Link to comment Share on other sites More sharing options...
naru2 Posted October 6, 2018 Share Posted October 6, 2018 Headlight relay has nothing to do w/it. Fan wiring goes thru the firewall twice. Firstly on the way to the ignition switch,then back out from fuse #4. Quote Link to comment Share on other sites More sharing options...
old sub freak Posted October 14, 2018 Share Posted October 14, 2018 so ...did you fix it? I just went through the same dance...No heater fan ,wipers or radio..messed n tested with fusable links ..Then out of the blue everything works...Till this morning turned the key to on and again all is working.....then i started it and nada.nothing !! So i gentley wiggled the key while it was warming up and ..Bingo everything works again..must be the contacts in the ignition switch...Now do i replace it or hope i can clean the contacts and go on with life haha have fun with your new ride..Great Rigs !! Quote Link to comment Share on other sites More sharing options...
Flyerborn Posted May 21, 2019 Author Share Posted May 21, 2019 Kind of a late reply as the ol' Soob took a back seat to my 1st Gen RX7 project in October, but got some time to play with the wiring again and found my issue but cannot tell you exactly what happened. There is a blue and yellow 2 pronged connector on the passenger side of the radiator that was blocking the power from wherever it was coming, heading up to the relay mounts on the passenger shock tower. Some dirt had gotten in there pretty good and caked the connection and I ended up having to cut it out of the system.After wiring it all back up I cleaned the yellow wire going to the thermo switch, grounded it, and lo and behold the fan kicked itself on! I put everything back together and decided to try and test it again, but.... nothing! Long story short, there are two relays that seem to be controlling the fan in my car. When I ground the thermo switch connector, the center relay in the tri-stack on the front of the shock tower *clicks* and the fan will come on, BUT there is also a relay on the back side of the passenger shock tower with a 4 wire connector going to it. (2 yellows, a blue, and a black ground strap.) If I mount the ground strap on to a grounding point and trigger THAT relay, the fan will not run at all. Basically, if the relay behind the passenger shock tower is triggered, that center relay on the front of the shock tower will still click, but the fan will not power on. Haven't exactly figured out what each relay is yet and my wiring diagrams don't show that relay behind the shock tower for some reason, though it looks factory. Not sure what that relay is all about yet. Basically, the fans work fine now, I've just got a little more troubleshooting to do. Best of luck to ya! Wanted to follow up since I hate leaving threads open in case others stumble across it. 1 Quote Link to comment Share on other sites More sharing options...
el_freddo Posted May 21, 2019 Share Posted May 21, 2019 One of those relays behind the strut tower is probably the AC compressor clutch power relay. On the older models (BRAT/Brumby) if you’ve got the headlights on it will cut the second relay to save power - and is possibly designed to suspect that it’s cooler during the time of day when lights are needed. Not always the case in Oz! Cheers Bennie Quote Link to comment Share on other sites More sharing options...
aba4430 Posted May 27, 2020 Share Posted May 27, 2020 On 5/21/2019 at 9:34 AM, el_freddo said: One of those relays behind the strut tower is probably the AC compressor clutch power relay. On the older models (BRAT/Brumby) if you’ve got the headlights on it will cut the second relay to save power - and is possibly designed to suspect that it’s cooler during the time of day when lights are needed. Not always the case in Oz! Cheers Bennie Resurrection of a slightly older thread - My Brat behaves in this manner. When the headlamps are on, the aux fan does not work. I thought something was amiss with it, but if this is normal, I am good. Separately, I have been scanning fan related threads as my aux fan is getting ready to quit. I picked up this fan as a replacement. Am awaiting some relays, sockets and wires to be delivered and will install. Quote Link to comment Share on other sites More sharing options...
aba4430 Posted June 22, 2020 Share Posted June 22, 2020 Spal fan linked above installed satisfactorily in the Brat. No clearance issues. Fan assembly is sturdy and there is a tad more space between the water pump tip and the back of the fan. Swapped the original connector from the existing fan onto the Spal, using pin terminal removal tools etc. Works very well without any relays added. Quote Link to comment Share on other sites More sharing options...
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