The link you've posted -- you're just using that as a reference for what a bad board would look like, right? TCU and ECU of course are two completely different entities, right?

I guess at some point, if it looks like a duck and quacks like a duck, you pretty much have to go out on faith that it is, in fact, a duck, right? If the codes get thrown and the car behaves in the manner in which it behaves, even if the ECU looks "good", you have to step out on faith that it just might be "bad", right? You can understand my trepidation in pulling this thing only to have it not, in fact, be the problem.

Thanks so much for all your help.

** By the way, you got a quick link on how to pull that ECU? I saw you mention on another thread that it's an easy fix.

 

Yep, I put that link to show you an example of a bad capacitor.

The ECU and TCU are two different parts. The TCU and ECU are right next to each other.

That thread above is the exact procedure to pull the ECU.

If you go to the common diy thread on top of the gen tech help forum, you can click on the online shop manuals thread. From there, the honda-tech link has a 94 shop manual you can download as a free pdf. That has a ton of information on you accord.

 

An alternative is use a voltmeter to determine if the ECU is quacking when it's supposed to quack.

 

Well, I got the module(s) out this afternoon; TCU and ECU. I've pulled apart the ECU (taken the covers off), and I must say I'm a bit concerned, mainly because I was hoping I'd see some sign of a disaster -- scorch marks or blown up components or something -- and it looks pretty darn clean (to my untrained eyes). Man, I'm really gun - shy about replacing this thing before I KNOW if it is the problem or not. . .I know the codes I mentioned above were indicative of the ECU being bad, but how much can you count on a "bad" computer to tell you that it is, in fact, bad? Does this question make sense??

 

The TCU is indicating the ECU is bad. You can take a look at the TCU circuit board as well.

BTW, is your car an LX, DX, or EX? Put that information in your signature, so we don't have to look at your first post for car information.

 

I've replaced the ECU in my 94 EX twice and found nothing to indicate source of failure.

good luck

 

I was kind of wondering that PA -- why the D4 would blink if the problem was, in fact, an engine problem. Why not the CEL? Are they mutually redundant systems??

 

The TCU is giving error codes that it is not getting signals from the ECU. They are two different computers.

If you go to car-part.com and search for engine computers (sort by distance), you will probably find one nearby for an LX/DX with AT (auto transmission) for under $75.

 

So I'm probably going to go ahead and get a part from car-part.com. But here's the question I have -- so say I go down to one of these places and get an ECU from what would amount to a junked car that they bought or was brought to them or whatever. What's to stop them from selling me an ECU from a car that had the exact same problem as mine -- after all, it's not like they would somehow test these parts, would they? Does that make sense??

 

Most parts places will provide a 30-day warranty for good part. You loose your effort/time, but they will replace the part. Part of the risk/reward of a used part.

I've bought lots of used parts and only had a couple of problems w/ used ABS modulators. I had to put two modulators together to make one good part, but good news was I only had $50 total in them.

All parts can potentially "fail out of box" or infant mortality. I haven't seen that used parts are worse or better than aftermarket. OEM parts are usually a step up in quality, and for some parts worth the difference; head gaskets, critical bolts, water pump, etc.

good luck