painterdave Posted January 23, 2007 Share Posted January 23, 2007 I'm posting for my hubby- (he hates to type!) He just finished putting a Japanese engine in his 4x4 Justy( manual tranny) Everything was going great, but the fan didn't kick on until the temperature got pretty hot, right before the top of the heat gauge just before it went into the red. It also came on just for a second then stopped. It seemed to be spinning slower than it should be ( to me) Now the fan doesn't come on like it should, but WILL come on with it grounded to the battery. So here's what we've done: changed thermostat checked the thermosensor ( at least we think we did) he put a u-shaped paperclip into the holes of the sensor-- will that test it? Tested the wires into the fan- they are getting juice Now he's thinking it's something in the fan motor that it needs an exceptionally large amount of juice to work. A n electrician at his work said it could be the diode in the fan motor. Before we spend the money getting a rebuilt fan motor, I just wanted to check here to see what you guys think. Another question here. I know he can install a toggle switch hard-wiring the fan on the dash and bypass the sensing units, but we'd really rather not- everything about the car is nicely stock and I think that'll be a last resort. But why do so many Subaru's have that hard-wired fan? We've had 2 that had them.... is there really a cooling issue that can only be fixed that way, or is it just a cheaper/easier fix? Thank you so much-- Susie Quote Link to comment Share on other sites More sharing options...
nipper Posted January 23, 2007 Share Posted January 23, 2007 It can be the bearing in the fan motor is going, causing the motor to use a lot of current to spin the fan, and not doing a good job at it. I had one go on 87 GL drove me nuts til one day i noticed all the slop in the bearing. nipper Quote Link to comment Share on other sites More sharing options...
RONAN Posted January 23, 2007 Share Posted January 23, 2007 I just went through this a few months back. I ended up replacing the thermosensor and the temp gauge sensor, both located side by side on the back end of the block. I had the same symptoms as you described. Quote Link to comment Share on other sites More sharing options...
RONAN Posted January 23, 2007 Share Posted January 23, 2007 Another thing, if I`m reading your description right about the paperclip, turn the ignition key to on and see if you can honk the horn? I did something similar to this and fried my in dash temp gauge. If not, check the fuse to see if it`s blown since the radiator fan and horn are on the same feed circuit. Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 23, 2007 Author Share Posted January 23, 2007 I just went through this a few months back. I ended up replacing the thermosensor and the temp gauge sensor, both located side by side on the back end of the block. I had the same symptoms as you described. What is the temperature gauge sensor? The temperature sensor seems to be on the rt side of the block as you are facing the motor, is there another temperautre sensor in the car? I I can't seem to find much in my Chiltons It lists the thing next to the thermosensor as an EGR valve. Thanks! Quote Link to comment Share on other sites More sharing options...
Skip Posted January 23, 2007 Share Posted January 23, 2007 It sounds like you and hubby have a fair amount of auto knowledge. Some semantics do need addresses however. First a "thermosensor" is a device that outputs a variable signal based on it's temperature. (variable resistance in most cases, a variable voltage in others) These are used by the dash gauge and by the ECU. On the other hand a "thermoswitch" is basically an on/off switch which is controlled by the temperature. These are used to control cooling fans. Hubby should check the fuse for the fan although the statement about the juice being present, indicates it is still in an operable state. If he does not own an ammeter he can do a quick test of the fan by using a 10 amp fuse to "hot-wire" the fan to the battery - the fan should draw about 5 to 7 amps max. If it blows a 10 amp I would suspect the bearings or windings. It is possible the fan thermoswitch (TS) has failed. Older generation Subarus ran the entire control amperage through the TS and it's contacts would deteriorate over time. A new TS should be cheaper than a fan motor if it proves at fault. The elevated temp of closure is another indication of this. Sorry I have no info on the location, the TS in some Subarus was mounted in the rad. If the fans are controlled by the ECU as in Legacys this entire diatribe is not applicable. There is no diode in the fan motor that I have ever heard/read about. Hope this helps. Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 23, 2007 Author Share Posted January 23, 2007 It sounds like you and hubby have a fair amount of auto knowledge. Some semantics do need addresses however. First a "thermosensor" is a device that outputs a variable signal based on it's temperature. (variable resistance in most cases, a variable voltage in others) These are used by the dash gauge and by the ECU. On the other hand a "thermoswitch" is basically an on/off switch which is controlled by the temperature. These are used to control cooling fans. Hubby should check the fuse for the fan although the statement about the juice being present, indicates it is still in an operable state. If he does not own an ammeter he can do a quick test of the fan by using a 10 amp fuse to "hot-wire" the fan to the battery - the fan should draw about 5 to 7 amps max. If it blows a 10 amp I would suspect the bearings or windings. It is possible the fan thermoswitch (TS) has failed. Older generation Subarus ran the entire control amperage through the TS and it's contacts would deteriorate over time. A new TS should be cheaper than a fan motor if it proves at fault. The elevated temp of closure is another indication of this. Sorry I have no info on the location, the TS in some Subarus was mounted in the rad. If the fans are controlled by the ECU as in Legacys this entire diatribe is not applicable. There is no diode in the fan motor that I have ever heard/read about. Hope this helps. Hi- I'm sorry I forgot to post that we did check the fuse, and it is ok- horn still works, they are on the same fuse. I think he replaced it just in case even. So the thermo switch is what controls the fan- I believe he pulled off the one from the old motor and switched it out, but I'm not positive on this. The electrical diagram does show the fan being controlled by the ECU, but when my husband gets home I will print these responses so he can make more sense of the posts! The tip regarding checking the fan seems like a good one to try- Also I was wondering if the trouble codes could be of help in pinpointing the problem? I really appreciate the help- Susie Quote Link to comment Share on other sites More sharing options...
Skip Posted January 23, 2007 Share Posted January 23, 2007 Hi Susie, very nice of you to help the hubster in this endeavor. Now If this is true The electrical diagram does show the fan being controlled by the ECU then yes this would help. Also I was wondering if the trouble codes could be of help in pinpointing the problem? It is possible some of the wiring for the JDM is different than the state side model. The ECU would use a thermosensor (sometimes refereed to as a Coolant Sensor CS) to control the fans and it's wiring would be of utmost importance. If the wiring is incorrect and the input from the CS is missing or out of range, the ECU will show an error code via the CEL (Check Engine Light). Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 23, 2007 Author Share Posted January 23, 2007 Hi Susie, very nice of you to help the hubster in this endeavor. Now If this is true The electrical diagram does show the fan being controlled by the ECU then yes this would help. Also I was wondering if the trouble codes could be of help in pinpointing the problem? It is possible some of the wiring for the JDM is different than the state side model. The ECU would use a thermosensor (sometimes refereed to as a Coolant Sensor CS) to control the fans and it's wiring would be of utmost importance. If the wiring is incorrect and the input from the CS is missing or out of range, the ECU will show an error code via the CEL (Check Engine Light). What does JDM mean? Well, we did have a CEL at one point, in getting this thing going- right after he got the engine in and just firing it up that light came on-- the engine also smoked quite a lot for a few minutes. I don't know how he got the CEL off. I was sitting in the car turning the key/car on and off Yes on the wiring diagram that I got from Alldata at the library the cooling sensor goes into the ECU. Hubby says the guy that runs the Auto shop class says the fan shouldn't be the issue if it works when grounded to the battery. Hubby's a painter for the local school district. It'll be interesting to see what we find out when we get to looking at it tonight. Any other suggestions? I really appreciate it-- I don't mind asking questions for him because like I said he doesn't like to type,and I like to investigate things-- I really don't want a hard-wired fan, I think we can figure it out, but may need some opinions from others who have been in our shoes or know more about this stuff than we do! Susie Quote Link to comment Share on other sites More sharing options...
Skip Posted January 23, 2007 Share Posted January 23, 2007 Susie, JDM is short for Japanese Domestic Market as you said he installed an engine from Japan. The CEL will go out and the ECU will store an error code. The Alldata manual should give you a way of retrieving these stored error codes. Probably by connecting two similar colored connectors under the dash by the steering column. Since the light came on upon starting the new engine I suspect a wiring incompatibility problem. I do not mean to steer you away but you may want to copy / paste your original question on http://subarujusty.proboards20.com/ after registering there. I agree hard wired is not the permanent solution for you. Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 23, 2007 Author Share Posted January 23, 2007 Thank you- It didn't occur to me that the wiring may be different--- I'll post later on what we find out--Thanks! And I will post on the Justy board--Thanks for the link! Susie Quote Link to comment Share on other sites More sharing options...
Skip Posted January 23, 2007 Share Posted January 23, 2007 You are most welcome, happy to help what little we can, it's just that we do not get a ton of Justy questions here. Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 24, 2007 Author Share Posted January 24, 2007 So the error code is 14- which the Chilton's says is the Duty slave or some such thing that we can't locate in the book...? I also am questioning the brass fitting under what we thought was the thermosensor-- I hope I used the right term-- because it's brass it seems like it's related to the heat monitoring- are we wrong on what is what-- The chikton's only shows one thing there, not two like we have one has 2 wires, one has 1 wire. I think we should switch that out, but Hubby's getting frustrated so I w ill bring that up later, I registered on the Justy board, but can't post until I get approved :0) Anyone know whar that error code means? Thanks! Quote Link to comment Share on other sites More sharing options...
Skip Posted January 24, 2007 Share Posted January 24, 2007 do you have the old engine? Use the sensors off of it that match the old wiring harness. You should have recieved an email moments after you registered at the Justy board, may want to check your spam filters. Quote Link to comment Share on other sites More sharing options...
Skip Posted January 24, 2007 Share Posted January 24, 2007 Two other quick thoughts 1) the "Children's" manual is not highly thought of as it has been misleading many times. Alldata is a better bet. 2) Sorry I have no other reference . please double check the code. These are at this link ECU codes - 1988 and Later Models With Single-Point Fuel Injection -- CODE PROBABLE CAUSE 11 Crank Angle Sensor or Circuit 12 Starter Switch or Circuit 13 Crank Angle Sensor or Circuit 14 Fuel Injector - Abnormal Output 21 Coolant Temperature Sensor or Circuit 23 Air Flow Meter or Circuit 24 Air Control Valve or Circuit 31 Throttle Sensor or Circuit 32 Oxygen Sensor or Circuit 33 Vehicle Speed Sensor (VSS) or Circuit 34 EGR Solenoid or Circuit 35 Purge Control Solenoid or Circuit 42 Idle Switch or Circuit 45 Kick-Down (Detent) Relay or Circuit 51 Neutral Switch Continuously in the On Position 55 EGR Temperature Sensor or Circuit 61 Parking Switch or Circuit -- 1988 and Later Models with Multi-Point Fuel Injection -- CODE PROBABLE CAUSE 11 Crank Angle Sensor or Circuit 12 Starter Switch or Circuit 13 Cam Position Sensor or Circuit (TDC Sensor on Justy) 14 Fuel Injector No. 1 (Legacy, Impreza, Justy, SVX) 14 Fuel Injector No. 1 and 2 (XT, Loyale, GL, DL) 15 Fuel Injector No. 2 (Legacy, Impreza, Justy, SVX) 15 Fuel Injector No. 3 and 4 (Loyale, GL, DL) 15 Fuel Injector No. 5 and 6 (XT-6) 16 Fuel Injector No. 3 (Legacy, Impreza, Justy, SVX) 16 Fuel Injector No. 3 and 4 (XT) 17 Fuel Injector No. 4 (Legacy, Impreza, SVX) 17 Fuel injector No. 1 and 2 (XT-6) 18 Fuel Injector No. 5 (SVX) 19 Fuel Injector No. 6 (SVX) 21 Coolant Temperature Sensor or Circuit Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 24, 2007 Author Share Posted January 24, 2007 Hubby says he switched everything over from the old engine-- all the components are from the "American" engine, just the most basic engine is the Japanese. So we tested the fan with a 10 amp fuse and it tested out ok, fan worked, fuse was ok. I guess at first Hubby was thinking the wrong thing was the thermoswitch, so he will buy a new one - we tried the one from the Japanese engine but nothing changed. We will change out the other brass thermal thing,right next to the thermoswitch which i "think" goes to the temperature gauge- this must be the thermosensor. i don't figure it can hurt. I totally agree with you the Chilton's is not good. You said that the fan would be controlled by the thermosensor via tha ECu, but the Chilton's says the thermosensor only relates to the air/fuel mix as the temp changes. So hopefully when he gets these two parts the fan will work. If not then we think the only thing it could be is the wires or the ECU. Do you agree? I'll go to the library today and get what I can from the alldata re the codes. Ours is a 88 carbureted model. About the Justy board, I got the activation code, but now I get a message that a site administrater must approve my account before I can actually be a member- seems like a day should be enough time- keeping at it- Susie Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 24, 2007 Author Share Posted January 24, 2007 Oh and on the Justy forum I got the activation code but now geta message that says my account must be approved by a site administrator before I can continue-- :-\ Susie sorry about the double posting - i'm having probs with the editing feature Quote Link to comment Share on other sites More sharing options...
nipper Posted January 24, 2007 Share Posted January 24, 2007 Oh and on the Justy forum I got the activation code but now geta message that says my account must be approved by a site administrator before I can continue-- :-\ Susie sorry about the double posting - i'm having probs with the editing feature thats ok, the USMB site is being frustrating lately. If you dont get aproved quickly let me know ill post it, as i am on that board. nipper Quote Link to comment Share on other sites More sharing options...
daeron Posted January 25, 2007 Share Posted January 25, 2007 if you are having strange problems with the little java applet used to type up your posts on the board here, try this. Hold down the shift key, and click on "Refresh/Reload" in your browser. This clears the cache, and fixes little problems like not being able to click on one of the buttons in the text editor and have do what it is supposed to. I like to highlight any text I have already entered and copy it to the clipboard, just in case refreshing might make it disappear. Regarding your problem.. I know nothing about justys, BUT it sounds to me like you probably are on the right track in thinking you were initially wrong about which component was the thermoswitch. The thermoswitch is just a little plug that, at a certain temperature, flips "on" basically. the whole "paperclip" method basically just replaces the switch with a soild wire. A simple check to see whether replacing the thermoswitch will fix your problem, would be this: 1. take a short piece of wire, and crimp terminals that will plug in to the car's plug for the thermoswitch. (OR just use a paperclip, or bare ended wires.. just makes sure your jumper has good contact with the harness plug) 2. Take this jumper wire and plug it in to the car as if it were the thermoswitch. 3. Turn the key to "on" and the fan should come on full blast. If the fan does not come on full blast with this jumper wire installed in place of the thermoswitch, then the thermoswitch is NOT the problem. If your car is carbureted, it shouldn't have an ECU. Unless, of course, its the feedback hitachi carb.. but again, here we reach a point where my knowledge gets fuzzy. did they PUT the feedback carbs on the justy? i dont know. In any case, i highly doubt the ECU would control the fan.. this is an '88 justy, after all.. NOT exactly the "cutting edge" of automotive technology. Just being honest Anyone who knows more about the Justy care to chime in with a junkyard source of a fan? I know the EA-82 cars all had fairly good units, and the EA-81s with AC had skinny fans, right? any chance that a fan from another car would bolt up? Quote Link to comment Share on other sites More sharing options...
nipper Posted January 25, 2007 Share Posted January 25, 2007 Anyone who knows more about the Justy care to chime in with a junkyard source of a fan? I know the EA-82 cars all had fairly good units, and the EA-81s with AC had skinny fans, right? any chance that a fan from another car would bolt up? How about an aftermarket electric fan? nipper Quote Link to comment Share on other sites More sharing options...
daeron Posted January 25, 2007 Share Posted January 25, 2007 How about an aftermarket electric fan? nipper They were trying to avoid high cost. Hence my Junkyard suggestion, IF the fan is determined to be the culprit. Are aftermarket fans all that expensive? I have never even looked at them, beyond something in a relatively specialized catalog.. (motorsport auto, they sell Z-car stuff.. and things like POR-15, radiator fans, and other non-vehicle-specific type stuff, I presume they are [/i]probably[/i] more expensive than most.) Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 25, 2007 Author Share Posted January 25, 2007 So... here's what happened... we decided we needed to figure out which switch was which one should be a sensor one should be a switch- we knew one was to the gauge, one was to the fan. The fan tested good, ( see prior post) so we took out one of the brass sensors. We knew it w the gauge sensor, because the temp gauge went dead. So we took out the other one and did the paper clip thing ( previously hubby had thought some other sensor was the thermoswitch so had paperclipped it instead)-- TADAAAA!! the fan came on!! So we will get a new thermoswitch and as far as Iknow that should take care of the problem-- agree?? Susie Quote Link to comment Share on other sites More sharing options...
daeron Posted January 25, 2007 Share Posted January 25, 2007 Agreed. Simple emough, now that youve got it all figured out, right? that seems to be the case most of the time with these cars.. finding the failed component is the tricky part. Removing the thermoswitch will obviously drain your radiator, so you might want to buy some antifreeze while you are at the store and just change your coolant instead of catching it and re using it. Either way, make sure youve got a nice large drainpan handy when removing the old plug/switch. let us know how everything turns out, it sounds like you are on the road to a properly functioning fan. Quote Link to comment Share on other sites More sharing options...
RONAN Posted January 25, 2007 Share Posted January 25, 2007 So... here's what happened... we decided we needed to figure out which switch was which one should be a sensor one should be a switch- we knew one was to the gauge, one was to the fan. The fan tested good, ( see prior post) so we took out one of the brass sensors. We knew it w the gauge sensor, because the temp gauge went dead. So we took out the other one and did the paper clip thing ( previously hubby had thought some other sensor was the thermoswitch so had paperclipped it instead)-- TADAAAA!! the fan came on!! So we will get a new thermoswitch and as far as Iknow that should take care of the problem-- agree?? Susie Sorry I did`nt get back sooner. Been busy. I know what your going through, since I was there and done that. I suggest that you get a service manual like I did and throw away the chilton. The service manual has way more detail and simple in the troubleshooting department. After my calamity that matches yours in every detail, I got one of them and reading through on troubleshooting that circuit, saved me a lot of un-needed frustration and anger. With my problem, like yours, I went as far as taking the whole dash out thinking there was a fan relay hidden somewhere up under. Then after grounding out and smoking my temp gauge in dash from troubleshooting under the hood, I had to pull and replace the instrument panel. Your problem sounds like either the tempsensor or the thermoswitch. PM me if you need any further help. Quote Link to comment Share on other sites More sharing options...
painterdave Posted January 26, 2007 Author Share Posted January 26, 2007 Ronan, and all- We've had a service manual on order for about a month, but I guess it's back-ordered. Hubby got the part today, switched it out and everything ran like it's supposed to Thanks for all of you help- we really appreciate it! I'll snap a picture and post it sometime -- Thanks again! Susie Quote Link to comment Share on other sites More sharing options...
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