ezone

Generally,
The only people that know the cars are the ones that have been working on them, and only then after many years of experience.
JMHO, YMMV

iteadjoseph

Well, it was nice while it lasted. I was driving yesterday and my battery light came on. The car didn't go to limp mode, but I took it to the guys who originally gave me a new alternator. Today they call me and tell me the Check Engine Light is coming on and the dash is going crazy. They think it's a ... fried ECU.

I just got a new ECU three weeks ago and thought this was fixed. Why do you think the problem is reoccurring?

ezone

Nailed it.

I said this three weeks ago:
I'm guessing the answer would be a big "no".
You will continue to fry PCMs until the real problem is fixed.

These PCM's do not go bad for no damn good reason. The PCM is not at fault.
EDIT: I meant original parts. Anything from discount parts stores is suspect.


Read this, print this, and do what it says. Show it to the people that are "working on" your car. (Notice the quote marks there?)
http://www.enginebuildermag.com/Arti...tor_bolts.aspx


Or the "new" alternator is overcharging.

AND you need yet another PCM if this one doesn't live.


HTH

iteadjoseph

Ezone, I appreciate the response, though I still remain a bit baffled about what to do. When I had the new ECU installed three weeks ago, I also had a new alternator installed. I imagine they installed it correctly, and that includes tightening the bolts. What else could the issue be besides these bolts? Would a short somewhere in wiring have the same effect?

Maybe this provides a clue: When the dealer installed the new ECU three weeks ago, they also needed to replace the ELD. Do you think this points to a different problem, or does it still look like an alternator problem?

In the meantime, I've called the shop where my civic is now and have asked them to take a look at the bolts. I don't know if they'll find something, but it's worth a shot...

ezone

You apparently have no idea how wrong your imagination is. The entire reason that bulletin was created and released is because there are sooooo many people out there that can't get (roughly) three simple bolts tight.

You STILL have the same problem.
I imagine the work wasn't done correctly.
Can you tighten a few bolts correctly? Some people that own tons of wrenches can't do that.
Have you checked out checking/tightening those bolts yourself, as per that info I linked earlier?

No.
(Contrary to popular belief, not all wiring problems are "shorts".)

An ungrounded (or insufficiently grounded) alternator/charging system causes excessive voltage, this in turn "fries" the PCM.
This is a fairly well known issue with these cars, and it is well documented as exampled by the item I linked previously. The same info/bulletin is listed in all major repair info systems available to all shops that are willing to pay for info systems. However, the people employed by said shops must be capable of reading and using these info systems.
Many aren't...I am dead serious.

Many are called "parts changers" for good reason.







I reread your post here: https://www.civicforums.com/forums/p...10-post30.html
You don't mention anything about fixing the CAUSE of the "fried PCM" problem. Is this a Honda dealer? I really don't care where you had the car, sometimes the employees don't know much about the cars.

If you don't know who the rocket scientist in the shop is and ask for them personally, you are likely to get the next available person in line.....no matter how qualified they may be. Because everyone with a shoebox full of tools has the exact same abilities and talents.

I have a lot more to rant about on all this, but nobody really wants to hear it.


No. ELD is a common failure by itself. There is a bulletin about that also.

Who decided the car needed an alternator in the first place? And why?
Who decided it needed the PCM replaced?
It kinda sounds like you dictated the repair procedures, instead of letting them do their job: finding the real problem.

This is just a guess: Your story is sounding like the cumulative effects (circling the drain) of what should have been a simple diagnosis and repair (though it may be expensive) if someone had figured it out correctly in the first place and made the proper repair. That didn't happen, apparently.



Sorry, this turned into a huge rant.
EDIT: Removed parts of the rant.

iteadjoseph

I'll lay out all the specifics, ezone, that way you don't have to assume or "imagine" whether I dictated procedures. Listen, man, I'm not trying to make people rant--I'm just trying to get some help.

3 weeks ago: I was driving the car. Suddenly the battery light starts blinking. It then turns off completely and the CEL comes on. The car noticeably loses power and I try to get it to the side of the road. I actually pull into a gas station, turn off the car, and try to restart it. It takes some extra turns but starts.

There just happened to be a local garage just a quarter block down, so I drive the car there and have them check it out. They tell me that the alternator is not giving any voltage and needs to be replaced. They replace it, then tell me that it does not fix the problem. They tell me they have "exhausted all of their possible options," and that I should take it to the dealer.

I have it towed to the dealer. They don't look at it until the next day. In the meantime, I go on to this forum and find friendly folks like yourself who explain what the possible problem is. I write a note to the dealer service department explaining that the car might need a new PCM. The next day they call, telling me I should replace my alternator because the aftermarket one probably caused the problem in the first place (which was incorrect, since the new one had just been installed AFTER the problem happened), along with replacing my PCM and my positive wiring harness. Grand total would be $2200.

I told them I couldn't even possibly afford that right now, and explained that the alternator was just installed. The service guy backs off his original claim that I need a new alternator then. He also says I could probably go without getting the wiring harness replaced (he says maybe I could get the terminal done later), but definitely says I need a new PCM. I ask if they'll install a used one if I can find it. He says yes. I ask him to read me the part number. He says he can't read it because it's scratched off.

The next day I drive to the dealer and ask to see the part myself. The part number is clearly there, no scratches--so the guy lied to me. That was annoying. I drive to a used parts place, get the right part, and bring it back to the dealer.

After installing it, the service guy calls me and says I need the ELD replaced. They do that, and I'm back on the road, no issues anymore.

Fast-forward to yesterday: I'm driving and the battery light comes on. No blinking, just on. I figure I better get the car back to the garage that gave me the alternator because it probably has something to do with that. They check it out, and after a few hours, they tell me that the alternator is "fine." Also, the mechanic took the car for a drive and noticed that the CEL was coming on, the instrument panel was failing, and this was happening intermittently. They tell me to take it to the dealer because it probably needs a new PCM. I tell them about how I had a used one installed already, and I ask them what is actually causing the PCMs to get fried. They didn't know the answer.

Hence, I'm back on this forum looking for help.

Matt_75

ezone

I understand that, I just go off on a tangent sometimes. Sorry about that.

Part of what I do is like automotive forensics. I sometimes obsess over finding the root cause of a failure, it's part of my job.


I've got "3 weeks ago the alternator quit", "Joes Garage put an alternator on and now it won't run", and "towed to dealer", without knowing much else about what happened during that event and repair other than the person on the phone is a flake, and the tech was helpful.

(One issue I see/read now is that you could still start the car after the initial stall, that tells me the battery had not run dead while driving.......This leads me to think the PCM tried to fry at that time. Continued operation under excessive voltage causes permanent damage to the PCM.)

Fast forward 3 weeks to now, it sounds like it fried the PCM (or is trying to fry it).......maybe again, I can't tell.

Yes, I'm probably making assumptions that I shouldn't.


This entire time today, I have been trying to align the sections of your story with the known events that happen to kill these PCMs.


This entire scenario usually begins shortly after someone has work done that involves touching the alternator. Usually the timing belt.


At this point I can't tell if this mess started with loose alt hardware from prior work, or a cheap reman alt that failed, or the installation of that alternator.
For all I know, a big battery charger was connected and running while the engine was running or even just having the key turned ON, and maybe that could have killed the PCM at the first shop.

I'm trying to piece the puzzle together, even though it really does me no good. LOL

But the end result seems to be another fried PCM, so I assume (either correctly or not) the original root cause has still not been found and corrected.

(EDIT: Damn Bill Gates Operating System crashed in the middle of trying to write and edit the post...Yet another pizzmeoff thing for today.)

iteadjoseph

Hmm... the only thing I can think of is, three months ago I had new brakes and front rotors put on, and the emergency brake seized. They replaced the wire that runs from the emergency brake to the middle console in my car. Any culprits there?

ezone

No. Not from what you just posted here.


(Check post above, I edited it again some more.)

Matt_75

iteadjoseph

So the dealer claims there is a short in the instrument cluster and that the positive battery harness needs to be replaced. What do you guys think? Would this make the battery light come on and the cluster gauges go crazy?

Matt_75

Yes.

If it's shorting to ground/shield, all power in the car is going to ground/shield and that's definitely a bad thing. If they determined that's the problem, that's probably a cheap repair. If it were me, I'd let them replace it...if it were me. Corroded cables can cause all kind of problems.

iteadjoseph

I wish it were cheap! They're asking 1600! I'm thinking of not doing it, with this plus the amount I already put in three weeks ago almost equaling the value of the car...

Matt_75

1600 to replace the positive battery cable? Really? That seems excessive.

ezone

I would want an itemized breakdown (parts, part numbers, labor, outside services, every last dime accounted for in it, every step of the way) of that $1600.

Then I would want an idiotproof guarantee.
(Good luck getting anything when all that money doesn't solve your problem. They will keep guessing until you have no money left.)

I don't want to be paying for guesses or some rookies education.
And I think they are just guessing, at your expense.


Solid proof might be had from swapping parts with an identical donor car. Got any friends?


Ain't makin sense to me, I ain't buyin it......not without PROOF.

90% of the gauge cluster operates on DATA that originates within the PCM. Once the PCM is corrupted, all you see on the gauges is (the equivalent of) jibberish. (GIGO).
Proper gauge operation should be restored when the PCM data is no longer corrupted.
This was already evidenced when the last PCM was replaced and lasted 3 weeks, correct?

Suggestion: You said the PCM wouldn't communicate with any scanners, right? If someone is trying to blame the cluster, just unplug the gauge cluster and see if PCM communication is then restored to the scantool. (It won't be.)



Battery cable?
And what was the exact reason for it?
I can't tell from where I sit if they would make you buy an entire engine harness to get it.

I know some issues that can happen with corroded cable ends, but that should be a fairly easy fix without buying an entire harness.

You DO know you can purchase battery cable ends at any parts store for about $3.00 right?

Easily replaced. (Clean the copper wires in each cable before assembly though.)
Dirt cheap, and worth every penny of it. LOL.
There are several styles out there, but this seems like the most common.

TONS of cars out there using these.

iteadjoseph

Well, here's the latest fellas. Turns out one of my student's dad owns a repair shop. He has his electrical guy look at it. He replaces the instrument cluster and the new one is working fine. The only problem is the battery light is still on. He said the alternator is outputting correctly and the car is running perfectly. It's just that light that is still on. He's going to try and replace the ELD to see if that fixes the issue.

ezone

It won't. The ELD does not control the charge light at all.

The PCM controls the charge light, based on what it sees the alternator doing.

The PCM does not control the light directly though.


The PCM communicates with the gauge cluster through a data bus, and the cluster has a microprocessor inside it to decode the data and operate the gauges and idiot lights.


New or used? There are like a dozen different possibilities for this to be wrong parts that don't match your car exactly.




HTH

Herman Wiegman

I am just joining this thread... because my CEL is now on and my ECU is in limp mode.

Hmm.. I changed my timing belt two months ago...I probably messed up my alternator ground. Thanks for mentioning that.

My ECU ground lug was also corroded. I will clean these ground connections and then install a new ECU and reprogram it at the dealer, along with my keys.

Here are another two threads on the same fault / symptoms.

282685-need-help-diagnosing-ecu-problem

332229-2001-civic-lx-lots-problems

thanks for a great forum and good discussion..

HLNW

Jessica B

Hello, I have experienced a major breakdown with my 2002 Honda Civic EX 5 speed. It's been having some problems which include overheating. I know there is an oil leak. The shop cleaned under the car, asked us to bring it back in a day or two to locate the leak, bc it wasn't easily seen. Well, the car didn't make it. Hubby drove it to work and at the end of his shift, he tried to start it. He said it made a noise and everything cut off.lights, sounds, everything. The engine will not turn over at all. I've read this entire forum and the only thing I can think of is the overheating may have fried the ECU. My dad's going to replace it and then focus on the fix oil leak. I've had new cables put on already. One interesting thing I saw I this forum is that the timing belt may have contributed... I gag mine redone a couple years ago and I already thought it idled just a little too high (just over 1 rpm). Would you suggest I have the timing looked at?

Fivegorets

Colin42

Are you alternator bolts tight?

Fivegorets

JuniorDavis

I haven't changed my computer yet but I too have the hard kick when downshifting, battery light on, clicking on the passenger side of the dash when the car cuts out and restarts at idle.

ezone

Loose alternator bolts will ruin a PCM in a hurry.

The ruined PCM is just a symptom.