sirtokesalot Posted August 28, 2021 Share Posted August 28, 2021 (edited) so while i was driving home yesterday from work the at temp light started flashing and felt like the transmission was binding while turning. i just finished putting the tail housing back together on the trans and replaced the duty c solenoid with a known working one and the at temp light is still flashing. is there any other simple checks i can do or am i gonna have to pull the trans and swap another one in it did flash about 5 days ago as well and i ended up putting the fwd fuse in and it stopped flashing and went into fwd and i ended up taking the fuse back out on my lunch break and it was working again after that for the last 4 days until last night when it happened the second time and now even with another transfer solenoid installed that is known working i get the at temp flashing and it will not go into fwd anymore with the fuse. Edited August 28, 2021 by sirtokesalot Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 28, 2021 Share Posted August 28, 2021 Test the solenoid resistance through the sub-harness. Could be a bad TCM. If the resistance doesn't check out I would get a new solenoid and transmission sub-harness from Subaru. "Known good" used parts aren't worth your time. GD Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted August 28, 2021 Author Share Posted August 28, 2021 so i may have got lucky. i just pulled the tcm out of our 2001 legacy sedan yard car and plugged it into my 2001 outback fired it up and the at temp light shut off. guess the yard car is about to become full time 4x4. Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted August 28, 2021 Author Share Posted August 28, 2021 alright so i got the car all back together with the yard cars tcm installed and no more flashing light transmission is behaving normally. a side note im not sure if it was the issue or not because i but the bad tcm into my yard car and it is now not throwing the flashing light issue in the yard car so i dunno Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted August 28, 2021 Share Posted August 28, 2021 Very possible to be cracked solder joints on the TCU circuit board. Might work if you jiggle the connectors, etc. Probably needs to be reflowed. GD Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 13, 2021 Author Share Posted November 13, 2021 (edited) now that i got the shake fixed i see this becoming my new nightmare. every couple weeks i get an at temp light flashing and the car will spit out a code 79 from the at temp light. i did replace the duty c solenoid but still have the issue. for some reason i can get the light to stop flashing reliably by plugging an h6 tcu into the car starting it shutting it off then plugging the cars h4 tcu back in and the light will be off on the next start and stay off for a couple weeks again. how can i figure out whats going on? i do not think its the tcu as i have put another 4 cylinder tcu in the car already and has the same results. how can i test this sub harness? im not great with electrical testing more of a find a fault and replace the part person. i do have another transmission just dont really want to go through the hell of installing it. Edited November 14, 2021 by sirtokesalot Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 14, 2021 Author Share Posted November 14, 2021 New update it seems to be an almost constant problem now I had the light come on last night and was able to clear it with the TCU swap method that I described then this morning when I left for work it was flashing again and was able to stop it with the TCU swap method I described now I'm on lunch break and I could not get the light to stop so does so it has become a constant fault at the moment Quote Link to comment Share on other sites More sharing options...
bharch99 Posted November 14, 2021 Share Posted November 14, 2021 I feel you on this issue, i think i have the same ghost AT Temp problem....so I put a new trans harness on the trans, it was like 225$ from subaru, the reason i did this is because my trans was rebuilt by the factory around 40k miles ago (even though the car is 99 forester, i was noted on the car fax and the tranny has the rebuilt plate riveted on it still) so i know it's worth keeping...at the same time i put a new harness in i replaced the at temp sensor that sits in the pan submerged in A/T fluid. I was able to get the light from coming on as frequently as it used to but similar to your problem, it does still come on every once in awhile. I can't figure out what causes it, I've done the secret handshake spoob, and it just says at temp sensor but i already know this...so that's no help...I've also replaced my TPS with a brand new one from Subaru and checked all the solenoids in the trans pan and even picked up a second TCM like you and it solved the problem for a long time until it came back and now it does it when it wants to....i can almost be like coasting abt to stop then give it gas, and it's like i catch it in between down and upshifting and it'll set the light off, i think it's electrical in some way but really i can't tell...it doesn't do it every time but i could have just started the car and go not even 2 miles down the road and the light comes on, it's still cold! and it says AT Temp...so i know it's not the sensor this time, I've checked all grounds and even made more grounds on the engine and tranny to help...i wish i could offer advice but I'm almost in the same boat...I'd just say to check your grounds if you did anything with cables and like was already mentioned, make sure the plugs are tight together... Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 14, 2021 Author Share Posted November 14, 2021 Afternoon update driving home with the light flashing nothing I am doing is making the light stop flashing there's probably a good chance that I'm either going to just drive it until the transmission blows up with the light flashing or I might actually get the UMP together and pull the transmission out I don't know yet it's cold I don't want to change the transmission in the driveway Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 14, 2021 Author Share Posted November 14, 2021 just finished cleaning the garage out got the car inside likely going to just change the dam transmission out and hope for the best Quote Link to comment Share on other sites More sharing options...
bharch99 Posted November 15, 2021 Share Posted November 15, 2021 i hope this fixes it for you, also one other thing to add to mine is that when the light is flashing, as long as i drive the car over like 60mph, the thing rides in OD all day long, its usually slower speeds in between 30-50 that its acting up and holding the gear and hard shifting and so on, as long as i'm on the highway, going over 60, it drives fine for me...please let me know if swapping out, fixes it...if it doesn't then i'd def say that yours is obvs a sensor or ground or something that's waacked out. Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 ill update it later. currently i got the old trans out and the new one is bolted in and thats where i left it last night. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 15, 2021 Share Posted November 15, 2021 2 hours ago, sirtokesalot said: ill update it later. currently i got the old trans out and the new one is bolted in and thats where i left it last night. Nice work! You cranked that right out and in! Give me a tip - my 02 OB AT doesn’t want to mate up to the (tilted and slightly lifted) engine properly!? Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 (edited) Just now, idosubaru said: Nice work! You cranked that right out and in! Give me a tip - my 02 OB AT doesn’t want to mate up to the (tilted and slightly lifted) engine properly!? use a jack and a block of wood in front of the engine and jack the front end of the engine upward a little so the engine tilts back. i actually had to backtrack this morning trans is back out on the floor again and just swapped the torque converter from old trans to new one. turns out an impreza transmission has a smaller torque converter and wont bolt up to an outback flex plate. ugg im doing this on jack stands have a floor jack on the back of the transmission and using an engine house and a strap connected tot he front of the transmission jumping back and forth jacking each end up little by little until it lines up. this is the juggling act. Edited November 15, 2021 by sirtokesalot Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 so pissed right now just got it together enough to start it the dam light is still flashing. Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 well i pulled the tcu from the forester in our yard and the light shut off. i dont tihnk the issue is actually solved thogh Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 new problem. the 4.11 2001 impreza rear diff wont accept the 4.44 2001 outback axles. can i just get impreza axles or will the outboard end be different as well? Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 15, 2021 Author Share Posted November 15, 2021 i got lucky thank god i save so much stuff i had an h6 transmission and diff and thankfully the h6 rear diff was a 4.11 and will accept an outback axle. got it back together just took it for the first drive. seems ok for now. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 15, 2021 Share Posted November 15, 2021 2 hours ago, sirtokesalot said: so pissed right now just got it together enough to start it the dam light is still flashing. Good grief. What a mess. sounds like it’s all sorted now? I do have my engine blocked up and tilted back that’s the annoying part. Have no idea how many Subaru ATs I’ve pulled but this H6 is being a dork. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted November 16, 2021 Share Posted November 16, 2021 wow, talk about tenacity Quote Link to comment Share on other sites More sharing options...
bharch99 Posted November 17, 2021 Share Posted November 17, 2021 still working ok for you with the new TCM and tranny? Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 18, 2021 Author Share Posted November 18, 2021 (edited) so far the temp light has stayed off it drives alright seems slower with the 4.11 in it but i kinda expected that. shifts great when im driving around normally but if i have to floor it for a pass or hard acceleration like getting on highway it shifts very slow kinda seems wrong. its like it stops reving out dis engages the gear does a very slow shift then re engages seems like a second or 2 for it to complete the shift before it starts pulling again. but at normal speeds cruising it shifts almost instant at what seems to be a normal way. im not willing to change the transmission again at this point thogh so im running it like this. could this maby have been an effect of using the bigger torque converter from the outback trans in the impreza trans? i would have thoght a 90,000 mile transmission would shift better than the 180,000 mile unit i took out. the shaking steering is back after the trans swap as well. on a plus side i do like that it seems to shift at more normal times than my old one did and doesent wait around in 3rd or 4rth forever before shifting to overdrive. Edited November 18, 2021 by sirtokesalot Quote Link to comment Share on other sites More sharing options...
bharch99 Posted November 18, 2021 Share Posted November 18, 2021 thats a good question about the torque converter, i would think the bigger converter would take more to move to it but honestly i'm not sure how much bigger that one is compared to the one removed. I would just make sure you have enough fluid in it if it has a bigger converter then it may need more fluid to shift correctly. Man, I'm sorry that it's such a crapshoot for what you problem may be but I'm super glad that you keep posting updates to what's working and what's not. i get on so many of these forums to read past problems and people suggest things and then you never hear back for what worked and what didn't, you never find the answer because they never post anything else lol! At least it's running and will get you through the winter probably as well. Quote Link to comment Share on other sites More sharing options...
sirtokesalot Posted November 18, 2021 Author Share Posted November 18, 2021 (edited) fixed the steering shake by swapping the front tires left to right i guess i put them back on backwards from how i had them. not sure why that would cause the shaking though. transmission fluid is definitely full i re checked that many times during the filling process and after it sat for a while checked it again. the transmission i put in did sit for 5 or 6 years out of a car before going into mine. Edited November 18, 2021 by sirtokesalot Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted November 19, 2021 Share Posted November 19, 2021 (edited) maybe a flake of rust between hub and rim? Edited November 19, 2021 by 1 Lucky Texan Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.