xntryk1 Posted January 2, 2019 Share Posted January 2, 2019 (edited) 3 days ago, my 1995 Subaru Legacy L station wagon conked out while leaving my house. After which, it refused to start up. Just cranks and cranks. Subsequent tests indicate that it is getting spark, but it's not getting fuel. There doesn't seem to be any clicking sound from the relay under the dash when turning the key. Also, no sound from the pump (I removed the outer cover, so I could hear it better). I suspect the relay has gone bad after 220k miles. But it could also be the pump (among other things, as always). I want to test the pump to see if it will run without going through the relay. I've read lots of things about hot-wiring pumps with a jumper wire between the battery and one of the wires going into the fuel pump. But I'm just not finding anything that says/shows exactly WHICH wire that might be and WHERE exactly it's located. Like it's common knowledge or something. But it's not to me. I'm not a real mechanic. I just pretend to be one, when necessary. Surely, somebody can tell me how to do this as easily as possible. Preferably without getting into electrical jargon that boggles my mind. Any help greatly appreciated, as always. Edited January 5, 2019 by xntryk1 Add tags Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 2, 2019 Share Posted January 2, 2019 (edited) Well, there comes a point at which you either accept enough "jargon" (the actual word is "terminology") to get the job done, or you don't. If the words "connector", "pin", "wire", and "positive" are too intimidating, get a friend who can handle it to help you out. You have a choice of locations where you can feed power to the fuel pump. The best one for testing just the fuel pump is the connector beneath that cover you removed. IIrc, the fuel pump relay is in a nasty spot under the dash where it's a hassle to do this sort of thing (I have a '95 Legacy as well, so I can look if necessary). But first, do you have the correct (meaning the exact model and year) wiring diagram for your car? You're going to need that, and this is a good time to learn to read one. Edited January 2, 2019 by jonathan909 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 2, 2019 Author Share Posted January 2, 2019 Ha-ha! No, I can handle terms like "connector", "pin", "wire", and "positive". It's when we start getting into ohms, volts, resistance, etc. that I get lost. And no, I don't have a correct wiring diagram for my car. I'm hoping to keep things a lot simpler than that. When it starts getting into that stuff, I'll have to take it to a real mechanic. As for the locations to feed power to the fuel pump, the connector at the fuel pump is MUCH easier to access versus the relay stuffed way up under the dash. I'm saving that fun (relay) for after I determine whether the fuel pump works (or not) with a jumper wire. So let's say I try to feed power via the connector at the fuel pump. How would I do that? Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 2, 2019 Share Posted January 2, 2019 (edited) 19 minutes ago, xntryk1 said: Ha-ha! No, I can handle terms like "connector", "pin", "wire", and "positive". It's when we start getting into ohms, volts, resistance, etc. that I get lost. And no, I don't have a correct wiring diagram for my car. I'm hoping to keep things a lot simpler than that. When it starts getting into that stuff, I'll have to take it to a real mechanic. As for the locations to feed power to the fuel pump, the connector at the fuel pump is MUCH easier to access versus the relay stuffed way up under the dash. I'm saving that fun (relay) for after I determine whether the fuel pump works (or not) with a jumper wire. So let's say I try to feed power via the connector at the fuel pump. How would I do that? Don't worry, you're not going to need any electrical theory - or a mechanic. But you will need the diagram, because that's where you're going to see which pins on the fuel tank connector you have to connect power to. Assuming it's like the later ones I'm familiar with (I've never had to mess with the fuel assembly in my '95), there's a single connector that supplies power to the pump and sends the fuel level information back to the dash gauge, and you can mess things up if you power the wrong pins. Next, what is your power supply? Are you just running wires back from the battery, or do you have something else that can provide 12V at the back of the car for this test? [Edit] Here - go get this: http://jdmfsm.info/Auto/Japan/Subaru/Legacy_Outback/1995/1995 Legacy Wiring Diagrams.pdf and I'll walk you through it. Edited January 2, 2019 by jonathan909 1 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 2, 2019 Author Share Posted January 2, 2019 Yes, it's a single connector at the fuel pump. With 6 pins I believe (from what I've read elsewhere, haven't actually yanked the plug yet to verify that). I don't suppose there's a handy-dandy free resource somewhere that has wiring diagrams? Also, in a couple threads I've read, people have stated that there is a "red wire" running under the back seat (to the fuel pump) and this is supposedly another place where you can apply power. Have you ever heard of that? Power-wise, I just bought a brand new battery that I haven't installed, yet. The old one was getting weak, so I wanted to have as much juice available as possible. I was thinking of using that (out of the vehicle) to apply power to the pump. Does that sound like a good idea or not? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted January 2, 2019 Share Posted January 2, 2019 (edited) You unplug the relay to the fuel pump and jumper the two relay connector pins that have the large wires going into them. Test tor power first (while cranking). If you have good 12v and ground then jumper it and crank the engine - pump should run while cranking. There's a lot more to diagnosing the fuel pump control circuit but that's the first step. If it works but doesn't with the relay installed test the relay. If the relay is good then you will have to diag the relay control power and ECU relay ground circuits. You don't really need the pinouts. The big wires going to the pump connector are power and ground. The little ones are fuel level, fuel temp, etc. GD Edited January 2, 2019 by GeneralDisorder 2 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 2, 2019 Author Share Posted January 2, 2019 Thank you, GD. I haven't gotten to the relay, yet. First, I'm trying to check the pump, to see if it will work with the relay bypassed. If it doesn't work that way, it's probably a good bet that the pump has died - correct? That's what I suspect because I've read certain threads that lead me to believe old pumps (like those with 220K miles on them) can get hot and burn out - especially if one has a tendency to run the gas tank close to empty too often. As I've been known to do. If the pump DOES work with the bypass, my next step was to check the relay. Not looking forward to that part, as I've read that it's a royal pain to get it out from under the dash. Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 2, 2019 Share Posted January 2, 2019 (edited) Did you get the wiring diagram PDF I linked to in my previous post? Fwiw, my '95 rustbucket has 450K km on it - it got a new motor+gearbox a couple of years ago, but no problems to date in the fuel delivery department. Edited January 2, 2019 by jonathan909 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 2, 2019 Author Share Posted January 2, 2019 4 minutes ago, jonathan909 said: Did you get the wiring diagram PDF I linked to in my previous post? Fwiw, my '95 rustbucket has 450K km on it - it got a new motor+gearbox a couple of years ago, but no problems to date in the fuel delivery department. Got it. Thank you. FYI, my car isn't close to me. I couldn't get AAA to bring it all the way to my house because I've got a weird driveway. So I'll have to take notes and then go down and do the hands-on after lunch. Fire away! Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 2, 2019 Share Posted January 2, 2019 (edited) Okay, go to p.44 of the PDF, titled "13. ENGINE ELECTRICAL SYSTEM LHD model" (it says p.51 at the bottom of the page). There's your fuel pump on the left side of the drawing. Print this page - people who try to debug stuff like this on their phones drive me nuts. As you can see, the connector at the tank is R58. Look at the bottom of the page and they describe it. Pins 1 and 4 are the ones you're interested in, and the drawing says that the positive side (which goes to the relay) is LY (Blue + Yellow) and negative (ground) is B for Black, respectively. Don't ask me why they chose L for Blue; I think it's stupid too. Confirm that those are the wires that correspond to the correct pins. Unplug the connector. Connect pin 1 to the positive (+) side of your battery and pin 4 to the negative (-), and you should hear your pump run. There may be a little spark when you connect it up; as long as the pump is running, don't worry about that. But if you get a spark and the pump doesn't run, the motor may be seized/shorted and you'll start burning wiring if you leave it connected, so unhook it without delay. Be careful. If you short the wires together - even with a battery you don't think is very good - you're going to get some or all of: sparks, heat, melted insulation, burnt fingers, and damaged connector pins that will add to your repair job. I do electronic stuff, so I've got lots of little grabby clippy things around; if I didn't, I'd go to the junkyard and snip off one of those connectors with as much wire as I could manage to give me a "pigtail" connector to do these tests with. How you do it is up to you based on what you have around, how much of a hurry you're in, how close the nearest wrecker is, etc. Follow all that? Edited January 2, 2019 by jonathan909 1 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 2, 2019 Author Share Posted January 2, 2019 11 minutes ago, jonathan909 said: Okay, go to p.44 of the PDF, titled "13. ENGINE ELECTRICAL SYSTEM LHD model" (it says p.51 at the bottom of the page). There's your fuel pump on the left side of the drawing. Print this page - people who try to debug stuff like this on their phones drive me nuts. As you can see, the connector at the tank is R58. Look at the bottom of the page and they describe it. Pins 1 and 4 are the ones you're interested in, and the drawing says that the positive side (which goes to the relay) is LY (Blue + Yellow) and negative (ground) is B for Black. Don't ask me why they chose L for Blue; I think it's stupid too. Confirm that those are the wires that correspond to the correct pins. Unplug the connector. Connect pin 4 to the negative (-) side of your battery and pin 1 to the positive (+), and you should hear your pump run. Be careful. If you short the wires together - even with a battery you don't think is very good - you're going to get some or all of: sparks, heat, melted insulation, burnt fingers, and damaged connector pins that will add to your repair job. I do electronic stuff, so I've got lots of little grabby clippy things around; if I didn't, I'd go to the junkyard and snip off one of those connectors with as much wire as I could manage to give me a "pigtail" connector to do these tests with. How you do it is up to you based on what you have around, how much of a hurry you're in, how close the nearest wrecker is, etc. Follow all that? Yep, I'm with you. Got that page printed out and your instructions noted. Now, I've just got to find a couple grabby clippy things. I don't do electronic stuff, but I do have a hoarder's tendency to hang onto lots of little items that may or may not come in handy. Pretty sure I should have something around that will work. Unfortunately, I'm trapped at home for the duration with no junk yard next door. Thank you! I'll report back after I get a chance to do it. Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 2, 2019 Share Posted January 2, 2019 Be looking forward to a progress report. Also, please note my edits in paragraph 2 that aren't in your reply. Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 OK, finally got a chance to dive into this. First, the good news. I was able to verify that there is indeed a blue/yellow and black wire running into the plug. So those must be the ones that power the pump (on the left-hand side of the plug). But now I'm really wishing there WAS a Subaru junkyard next door, so I could find/use an old plug for a "pigtail" connector. Was hoping the plug worked the other way around, with the male end connected to the wires and the female end connected to the pump. But nooooooo (see pics). Since it's the other way around, I can't just plug paperclips into the holes and attach the battery to those (like I was planning). Instead, I'll need 2 tiny little plugs - which of course I don't have. Not to mention, it's almost impossible to see that end of the plug to make sure things get attached correctly. I can get my camera in there, but I can't get my head in there. So unless somebody has some ideas on how I can manage to attach the battery to the fuel pump without tiny little plugs, I'm back to my original question. Is there an easier way to do this? As I mentioned previously, I've read in a couple threads where people have stated that there is a "red wire" running under the back seat (to the fuel pump) and this is supposedly another place where you can splice in power. Before I yank everything out of the back seat (everything that used to be in the back of the car), does anyone know if this is true or not? Help! Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 (edited) Sorry, I can't help on the rumoured-wire front - I'd just find a way to connect to those (male) pins. If you can lay your hands on some small (e.g. 1/8") female "quick disconnect" crimp lugs, they may push onto the pump pins. Otherwise, I'd disconnect those three hoses and pull the cover (it's only eight nuts, so you'll have it off in a minute) and lift out the whole fuel pump and sending unit assembly. Then it'll be easier to test "on the bench". Personally, I'd rather do that than start pulling seats and chasing wires. Edited January 3, 2019 by jonathan909 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 Since it's a station wagon, the bottom of the back seat actually comes out fairly easy (after I get all the crap off it). As for yanking the entire fuel pump and sending unit assembly, I've already watched several videos about that and it does seem fairly easy (albeit messy). I'll probably have to resort to that if no other ideas are forthcoming. Here's a picture showing my attempt at attaching the smallest alligator clips I have to the plug. Managed to squeeze in the ground clip - flying blind. But there's simply not enough room to squeeze in the other one. Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 I have the wagon too, and I still wouldn't chase wires. There's no way you're going to jam two alligator clips of that size in there without shorting them together, so you should definitely snag a couple of the small quick-disconnect crimp connectors. (Photo credit: My daughter Becky) Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 Yeah, my problem is, I'm stuck at home - way out in the country - by myself. So I'm desperately trying to make do with what I've got on hand. Shopping for things isn't an option at the moment. Anyway, while I was pondering what to do about testing the fuel pump plug, I decided to go ahead and see if I could find the relay switch under the dash. OMG! Could they make that thing any more difficult to get at?? After removing the cover under the steering wheel. I finally found the green plug, tucked way up under the dash, behind all kinds of thick bundles of wiring. It's practically on the inner side of the left front wheel well!That's going to be whole 'nother challenge, if I have to end up replacing that. Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 (edited) I empathize - I'm way out in the country too, but with the advantages of a ridiculous stockpile of stuff to work with and (usually) an extra car to get about in for things like this. If you're CAREFUL, you can run a quick test (that's all you need right now) with that alligator clip on the lower pin (as shown in your photo) and just a piece of wire for the upper. If the wire is something like AWG 16 or heavier, cut the end flush. The insulation will give you reasonable protection from shorting against the clip, but the exposed end will still make contact with the pin. Remember, you only have to make contact for a few seconds so you can hear the pump run (or not), so you don't have to be elaborate about this. As for anything under the dash, yeah, that's how it is. I'm sure it appears in one of Dante's circles of hell. Edited January 3, 2019 by jonathan909 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 Ha-ha! Look what I discovered in my little box of misc. electrical connectors. So back down I go... Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 Hubba-hubba! Zackly what you need. Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 Absolutely no sound from the fuel pump. Had good solid connections at both the battery and plug. And I verified that the new battery did in fact have a good charge (it did). So correct me if I'm wrong, but doesn't that indicate a dead fuel pump in need of replacement? Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 (edited) That's precisely what I'd take it to mean. Sounds like it's time to pull that cover and get the old one out and confirm it's dead. What's your plan for getting a replacement? Edited January 3, 2019 by jonathan909 1 Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 Alrightee-then. Next step: yank the fuel pump and sending unit assembly and verify exactly what kind/size of new fuel pump I need. From what I've been reading/seeing, there are at least 2-3 possibilities. A couple different sizes and one with a plug connection and another with 2 post connections. Once I see which type/size I've got, I'll get that ordered and hopefully that will solve the problem. Then, I'll just wait around for the next old part to die. Thank you jonathan909 for your invaluable assistance! Quote Link to comment Share on other sites More sharing options...
jonathan909 Posted January 3, 2019 Share Posted January 3, 2019 My pleasure entirely. Sounds like you've got it well in hand. I've only messed with these things in 99-02, so I don't know which style of pump the 95 has. So are you now stuck at home, bingeing a TV series, until the UPS man shows up with a package from Rock? Or do you have some local support that might give you a lift to a local parts source? Quote Link to comment Share on other sites More sharing options...
xntryk1 Posted January 3, 2019 Author Share Posted January 3, 2019 (edited) Ha! No such luck on the local parts source. But I will shop around for the best deal online and then wait impatiently until it gets here. That's IF I can even get this beast out of the gas tank! Any tips/tricks on removing a stubborn rubber fuel line? I've got everything else disconnected, but can't get the main (middle) fuel line off. I've twisted it with pliers and it does turn. But it's not wanting to pull off. And as you know, there's not much room to work with there. I'm just trying not to damage it and make matters worse... Edited January 3, 2019 by xntryk1 Quote Link to comment Share on other sites More sharing options...
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