Will a Main relay solder issue cause the trans to start off in 2nd gear and then quickly shift into 1st and then carry each gear a little farther before it shifts? It is obviously winter and it seems like when it is hot inside the car it starts acting up. when I shut it off and then go back to drive it ...lets say the next day or even a few hours later it doesn't do it??

1991 honda accord lx

 

I'm not aware of any linkage between MFR and trans shift performance.

However, there are numerous reports of defects in TCM for 1990-1993 Accords and cabin temperature increase could cause solder jt defects to appear.

Does D4 light ever blink? Do you hear clicking from interlock control box (one of symptoms). See attached TSB.

good luck

 

No the D4 light never blinks and no clicking from the solenoid. The "S" light has been on ever since I bought the car. The previous owner had the tcm repaired by a place in Florida. The trans was bad when I bought it. I replaced the trans and the S light was still on. I have checked all the wiring and switch and all are ok. I sent the tcm back to the place that repaired it because it was still under warranty and they said it was fine. I asked them if it was for my car with the sport shift and they said yes. I am beginning to not believe them. I think I read on here that if the tcm from a car without spport shift was used in a car with sport shift that the light will come on. the light only comes on when you put it in D4 and in D4 only.

 

In your case the S light is equivalent to D4 light in later models.

I could not find any description for S-light on steady except the TSB I sent.

Suggest resetting TCM by pulling the backup fuse (under hood fuse box) for 20 secs and see if S light blinks or returns to steady.

If resetting TCM improves performance temporarily, the TCM is likely faulty as you suspected.

ebay and car-part.com are potential sources of replacements, if you decide not to pursue warranty repair of your TCM.

good luck

 

TCM is out of warranty. Im gonna open her up when I get a chance and I will try resetting by pulling the fuse. thanks

 

Well I opened the TCU and the resistors and capacitors have been replaced as I expected by the people that rebuilt the unit a few years ago. I couldn't see any visible/burns damage. I put it back together and reset the computer by pulling the back up fuse. We will see what tomorrow brings. Can anybody tell me what tcu I need in that car. It has the sport shift option. I'm almost certain they put one in it that does not have that option. How common is the sport shift option anyways? Do they all have it? If I give someone the vin can they tell me what TCU goes in it and tell me if I have the wrong one?

 

Are you looking at Engine Computer (PCM) or TCM? TCM is separate unit. See following link for pics and part nos.

Honda Automotive Parts

PCM may be fine, but TCM is more likely to have problems.

good luck

 

There are two ways to look up parts. You can start with your vehicle and look up the TCU to find the proper part number. And/or you can enter your TCU part number to view cars using that TCU. Both pieces of information are helpful. Going from part number to vehicles, will show donor vehicles from ebay and junkyards.

Hondapartsnow.com will pull up all the vehicles using the same part number. I can't remember if the link TexasHonda posted does this.

remember to click on the links on the bottom of that site to view the specific vehicles, because 90-93 is only the generation. Clicking on those links will show 91 LX/DX accords. Hope this makes sense.

 

92 (and probably 93) Accords did not have sport-shift (or automatic seat belts, thank goodness).

 

I am looking at the TCU. It has been repaired before. I wish I would have wrote down the number on the unit. It looks like the people that rebuilt it put a sticker of there own over the factory sticker. I wonder if it is the same part number as it is under there sticker I will pull it out again tonight and get the number off of it. The S light is on all the time only when in D4 has been ever since I owned the car (3 years)