92 EX A/T shifting problems. TCU?

[Honda_Lady]

first off i wanted to say I did not come here just to ask for help on my car. ever since i got my car (and first started noticing how many others were still on the road) I have kept an eye out for them. I came here mainly to have others with the same car as me to hang out with, learn from and perhaps even share my knowledge.

i have a 92 Accord 2.2L EX with an automatic transmission. 2 and a half weeks ago (August the 21st (Sunday)) the D4 light started flashing GREEN. I also had a major fluid loss as well as shifting problems. I put fluid in twice that day and it hasn't lost any fluid again since (i check it every day) and for the most part has shifted fine until this past Saturday.

I called my Honda friend that i used to work with and he said 2 things. 1) the transmission was gone 2) to pull the "back up" fuse to reset the codes and see if they came back on and was going to look up the codes for me when he went to work. the same week on Friday the light started flashing again. i pulled the codes that time and found a site that had a list of codes. i had 2 codes. according to the list i found my 2 codes are the following: 7 -Shift Solenoid 'A' circuit open or shorted. 15 -Kick down switch circuit shorted. now i had to look up what a Kick Down switch did. i know where the shift solenoids are and what they do. at first i thought maybe they were shorting off each other. i could only manually shift the car and it still flaked out sometimes going into second and third. putting it into D4 it wouldn't shift at all on it's own. i pulled the "back up" fuse again to reset it and now it shifts fine again. if it was something other then the TCU would it reset it self twice by pulling the back up fuse?

this was the second time i had a shifting problem. coming up on a year ago i replaced the TCU due to a no shifting problem. the GREEN light around D4 just stayed on no matter what gear i was in. i put a used TCU into the car. in searching on the internet, i have found that the TCU's are usually the reason for shifting problems in these cars.

Resetting the codes temporarily fixes the problem for several days with no problem at all shifting. Could this shifting problem also be caused by the TCU?

Any assistance would be greatly appreciated. Thank you all so much in advance.

[djscoonf22A6]

that same shit happened to me it is the tcu

[bobbycos]

that same shit happened to me it is the tcu

90 lx here and it was the tcu


but make sure that it is the tcu first

use the search function and search the threads

[Honda_Lady]

ok thanks guys. i will search these threads before i replace the TCU. i already thought that because it temporarily fixes itself when the back up fuse is pulled that it wasn't anything else but i will make sure before i replace the TCU again.

EDIT: i searched these forums for other shifting problems and none of them match the same symptoms i am having.

[deevergote]

If your D4 light is flashing, it is telling you that your TCU is throwing an error code. The thread at the top of this section marked "Read Here First!" tells you how to read and interpret the code (oddly, NOBODY ever reads that thread first, because we get one of these threads a week.) If the D4 light is flashing, chances are good that the TCU is just fine, and it's doing its job reporting the real problem. If you replace the TCU, you'll probably just be wasting your money. Don't kill the messenger. Fix the real problem.

However, to be sure, open up the TCU and look for burned components. If things are burned, the TCU is bad.

[Honda_Lady]

i'm not just some ditsy blond here. i know what it's like when a vehicle speed sensor goes out. i know what it's like when shift solenoids go out. i may be new to Honda's but i learned a ton by working on them every day for a year as well as fixing my other cars before i got my Honda.

my question was "if it was something other then the TCU would it reset it self twice by pulling the back up fuse?" if it would do that how long would it take for it to fail a test again? mine takes almost a week to fail a test again. if it was something like shift solenoids or something wouldn't that happen sooner? i know that every time you turn the key on, the computer runs a test on everything by sending it a signal and waiting for that parts "response". I went to school for this and i am constantly reading to learn more about how cars work.

I looked at that thread. i'm not like most people when it says " Read Here First" that's exactly what i do. i always try to find out what a forums rules are as well as seeing if the info i'm looking for is already in a thread somewhere before posting my own problem if my question wasn't answered.

now as far as the TCU is concerned: i have found many cases where it was bad, and after they replaced other parts finally decided to replace the TCU anyway. they had checked inside the TCU and found no damage but found that it was bad in the end anyway.

[psawall]

The answer is no, probably not. So pick up a used TCU if you've got $50.

However, if you want to do further testing, check resistance between each of the pins leading to the solenoids and ground. They should both read 14-16 ohms. If the readings are not withing spec, solenoids are junk. You can even go a step futher and put 12v to each of the pins and listen for a clicking sound. No-click, bad solenoid. The shift solenoids are the lower pair on the transmission, the top pair are lockup solenoids. But like I said, this is probably not the issue, mostly likely the TCU. But if you get bored waiting for the TCU to come...

[Honda_Lady]

ok thank you psawall

[deevergote]

I apologize. I was on my way to work when I replied, and I missed the middle part where you said you checked the codes. All that stood out to me was "my D4 light is flashing" and "is my TCU bad?"
We have at least one thread a week like that, if not more... and people ALWAYS assume it's the TCU. I suppose I got ahead of myself.

Usually, a bad TCU will show burned resistors... and people who have replaced those resistors properly seem to have been able to salvage the TCU for very little money. I can't recall any cases where a TCU was confirmed bad without visible damage.


Honestly, rather than spending $50 on a new TCU, look around for local people (you can't post in the Regional section yet, but you can browse, and PM the members. We have MANY members in Florida, and they're a tight-knit, knowledgeable group that will be more than happy to help.) Find a member with an automatic CB that is working properly, and see if you can borrow their TCU. That way, you will KNOW that the TCU you're using is good (a used one from ebay or a junkyard may or may not be good), and you'll be able to determine for sure if the TCU is your problem. If you still get error codes with a known working TCU, then the problems reported in the codes are likely to be correct. If you get no codes with the good TCU, then I'd say it's safe to assume the TCU is the issue.

I have very little experience working on automatic transmissions myself, but I've heard of people removing and cleaning the solenoids, which fixed many shifting problems and error codes. I would give that a shot, as well as cleaning the electrical connections on them.

Simply pulling the "backup" fuse only helps clear codes once the problem has actually been fixed...

[Honda_Lady]

it's ok deevergote. trying to get out the door on time (atleast for me) usually gets me sidetracked and not reading through stuff completely.

i will at the very least check the solenoids and see (through PM) if anyone is in my area to perhaps borrow a ECU to see if that is the problem. thank you very much for your info

[HardInThePaint]

What was the cause of the fluid loss?

[Honda_Lady]

i don't know. i hadn't checked it in a while and perhaps it had slowly burned some of it and i didn't know it because i wasn't checking it every day up until the light started flashing. since i hadn't checked it in a while, maybe the reason i had to add some twice was because it had a few bubbles in it from getting low and it had to run some to fill those areas back up. i had never had a problem with loosing fluid before but i know now that i definitely will keep a much closer eye on it.

[Honda_Lady]

so today after no problems for over 2 weeks the car wouldn't shift again. pulled the back up fuse again and it shifts fine again. as far as i know this time the D4 light didn't start flashing like the last 2 times. my mom drives the car at night for work, and didn't see the light flash, and i drive it during the day and the light didn't start flashing. (sure wish i could afford a TCU )

[budget street]

well you are fortunate this is not an internal tranny issue.
i have had similiar experience with the tcu in my 91 ex. every thing is fine for a few days or a week and d4 starts flashin tranny wont shift, i have accumulated at least 5 tcu and they are intermitent failures. when it starts acting up i switch it out for another. i converted the car to manual so no more issues for me.
too bad you are not closer i would let you try out my tcu's
im sure you know this and at the risk of offending you, the honda auto trannys are very diffrent than a domestic tranny so the tranny fluid is checked with the engine off.

[Honda_Lady]

yes i am very glad it is not an internal issue. i would be so screwed if it was. yea too bad your aren't closer. oh well i found one that is only $20 but would have to also pay for it to be shipped since it's over 100 miles away. before i buy it though i want to talk to these people that have it and find out if the thing is good quality and if not look else where.

yea i know that about the fluid. Honda just has to be different lol