well at least ur getting a loaner now....good luck buddy

 

sounds like you had an epic failure

 

That makes since. Random acceleration/decelleration is more important then the bcm i think too.
Its possible that the sensors for the gas pedal are messed up/shorting on something, or somehow picking up false signals and sending it to the pcm. So when it accelerates/dedcellerates, its becase the PCM thinks that your pushing the gas?

 

Your lucky as **** you took a picture. Other wise they would just have kicked you out the door. Glad they're taking you seriously. Hope they figure it out soon.

 

gas pedal has a redundant PAIR of sensors in completely different resistance ranges, not only that but they are calibrated every time the key is turned both on and off. FUEL RANge xxx and parking BRAKE is my guess.

Anyways, there is one way above others that can cause this issue, ground. If the ground signal is not clean, and as low ohm as possible this can and will mess with all sensor readings. Furthermore if say the battery ground is not exactly tight, partially shorted, it would certainly be possible. Another possibility is an alternator rectifier about to go out AND a bad battery ground.

Toyota's issue has nothing to do with the carpets and brake pedals...


allow me to amend my statement.

I confirmed that IF the ground was shorted you would have a false reading for your fuel level AND possibility of things like messages for your parking brake. Why your display chose to show it like that could literally be a high frequency signal in your body ground that the BCM read as conditions occurring hundreds of times a second...total speculation. For this same reason it would be plausible that the ECM had no idea what the actual throttle position was. If you change the input value of the sensor from 5 volts to something less or more the output will be skewed...akk rambling.

 

I have a buddy that works at a GM dealership that has done the recall(pontiac Vibe) and agrees with you. He says those shims are total bullshit.

back to the OP, where there any other lights on??? I wonder if something is taking down the bus signal?

 

no other lights were on.

heres a question tho.

If the BCM is fried, that is the reason it is throwing the "wrong code" that messed up. so wouldnt replacing it allow the car to figure out what's actually wrong?

 

I occasionally watch C-SPAN...I know, anyways, I watched the independent engineer testimony that stated the problem was not nor could it be the accelerator pedal, this is why Toyota is unable to sue their supplier. He went on to state that the only probable means to cause this is to change the input voltage value AFTER the accelerator is calibrated for the run cycle. Furthermore he stated there are only two ways this is possible. One is a Ground Fault either a short or high frequency interference or an ECM failure. Dodge had this problem in millions of vehicles and everyone blamed it on bad transmissions. But every single time you could replace the PCM and go on with business. There is an output bus on every ECM that is a +5CDC regulated output, this value is checked hundreds of times a second and compensated internally so even if the value goes up or down it will not change any sensor values whatsoever.

I've thought about this for a while now, I am gonna go with my gut based on the fact the BATTERY was changed, and somewhere due to the replacement or the fact the car had to be jumpstarted I would assume at least to get it to the dealership, It's entirely possible the load on the alternator shorted the internal rectifier and is throwing high frequency interference at the ground system. It's kinda like trying to have a conversation while someone is shouting to someone else right next to you. Your engine probably couldn't make heads or tails of the sensor readings.

At this point the dealer only has one option if they cannot quantify your problem.

They must replace both the ECM for your acceleration AND the BCM for your dash display faults. I would go even farther as a tech and ensure the basic root causes for this condition are ok, including checking the harness connects, reseating them as necessary, even checking pinouts. I'd look at the battery compartment, the batt ground, engine ground, I'd certainly do a ohm test between components to rule out a bad ground somewhere. After that I'd drive the car to verify it's ok, I'd probably go so far as to hose the engine's harness while it's running to see if that reveals issues I didn't find while it's bone dry. The problem is they won't do any of that.

Certainly a great time to point out the battery was recently replaced and if possible to check for a ground, and before it goes any further I would from this point remove your amp and subs and all associated wiring.

 

Win.

 

i had to boost the car every day in the winter time. got the battery replaced over a month ago by GM...

 

I think your problem has been identified then. Replace Alternator, verify no conditional recurrence, continue mission.

 

so essentially i should call the tech at GM and tell him about this finding?
wont this hereby void my warranty? My sub drained stock battery and blew out my alternator, which caused damage to BCM and probably ECM as well?

bump for update

GM called

Tech told me that they have every personnel checking out the car. The strange thing is, according to the tech, is that there does not seem to be any codes at all, not even any records of any bad codes being thrown, such as the o2 sensor problem I was having...

They told me their were ground issues but nothing to serious, alternator is fine. They also said that the BCM is fine. Tech speculated that the problem was being caused by my info button on the steering bezel, because it is no longer functioning properly, and it is mixing up phrases on the DIC. He said there is a chance it is causing my cruise control to act up, which is the reason why the car is accelerating abnormally and is not decelerating. He will be replacing that. He said that he contacted other GM's and they have no idea what it could be. I was also told that I will get the car back tomorrow morning, and hopefully things go well. They said if anything at all feels weird or another code gets thrown, to come back to GM immediately.

I did ask why they dont just replace the BCM due to weird codes and the ECM for acceleration problems, and he replied that he would love to replace everything on my car, but since their are no codes that are being shown thru the BCM or ECM, he believes that the problem would still be there, even if they were replaced.

I am rather disappointed in the results. I am also disappointed that GM is giving me the car back without any idea of why the car is acting up, and is hoping it is the info button. Hopefully, it is, and is nothing to serious. I am just worried for "the worst" if i am driving on lets say the highway or a school zone. As for liability issues, if I get into an accident because of something that was not repaired, GM will have major problems. Again, lets all hope its the info button...

Thanks for all the sub's, kinda hoping I could give you a better conclusion :P

Stay sub'd anyways, Ill let you all know how the car is and if anything acts up. You've all been a big help SCARING me :P

Thanks guys!

Matt

 

Maybe its a priority issue. The BCM isnt programed with "Fuel Range Low" vs "Parking Brake" properly, so its trying to show both at the same time.

 

that was my thinking...should you tell them about all that, absolutely not. While this should NOT cause any damage to the car other than eventually toasting your battery I wouldn't breath a word of it. I'm curious to see what GM says I hadn't even considered the info button although it makes ZERO sense, and now with the history being wiped from the ECM that would concern me as well, maybe someone knows if the history is saved when the batt is dead or not.

 

it could be saved depending on the type of memory storage it has. if i were you id make them give you a letter stating that they couldnt find what caused the random acceleration just in case something does happen you have that to take the liability of you but lets all hope it was a fluke in the system

 

I'm gonna go ahead and say this is practically epic. What happened was a number of things at the same time, DIC message not withstanding you hadn both erratic acceleration AND the computer was modulating your brakes for you...effectively removing your ability to use them. So you had a stability control error, an ecm/sensor error, a DIC error and to top it all off they haven't figured out the root cause.

Perfect candidate for lemon law if you ask me, and I'm not sure if GM can't find the cause if they'll even allow you to have the car back, there is substantial liability of any shop giving a car back to the customer with an undiagnosed safety problem. I don't agree that milking them for a new car is a good idea, and they won't do that either, but it would concern myself since I'd rather not crash into anyone and have to explain to them the car did it not me...or have anyone hurt/killed over this.

 

^^
agree 100%.

However, GM told me they would call me by 9 AM to get my car. It's 1:36 PM, and there was no call received. So we will wait and see what happens.

 

What the ****...crazy

 

I've been following this thread the last couple days, I've read about people subscribing to them. How do you go about doing that?

 

Once you post you usually are subscribed. But click thread tools at the top, and select subscribe.

 

Nice, thanks.

 

bump.. update time

sorry to keep everyone waiting so long.
GM does not want to give me my car back because they cannot figure out whats really wrong with the car. They said that the bezel that has the cruise control and info and all DIC controls was replaced, but they do not feel it is sufficient enough to give me back the car, hoping that the problem is fixed, due to speculation. This said, I had a meeting with the manager, and hes leaving me the loaner car for a little bit (grand prix). He said it's difficult to try to fix an issue that shouldn't and doesn't exist in the system, and until we can figure it out, its best you don't have the car... yata yata yata, anyways, I wont have my car back for a while, but ill keep everyone updated. Next update will be on Monday when they start working on my car again!

Thanks everyone for your patience

Matt

 

i kinda figured they wouldnt give it back. i wish mine would have a short or something and burn to the ground... i have full coverage plus the mods are covered.

 

For insurance purposes as a shop (I do field repair of logging equipment I know this all too well) if the customer presents an issue that involves his/her safety in use of the vehicle, you cannot give that vehicle back to them without a repair to satisfy the diagnosis whilst properly documented. An example of this, I had my master cylinder go out in a Dodge, the replacement was faulty, I had to prove that I installed it correctly, tested it correctly and returned it to service as prescribed, when it failed had I not documented the job I would have been liable.

For the above reason they will NOT give you your car back until they can prove they took every step to eliminate them as liable if this was to cause an accident. That of course doesn't mean they'll actually fix it though, as unfortunate as that is. I am STILL of the belief the alternator's internal rectifier is the root cause.

 

^^
i understand completely..
I want to notify GM to check my alternator but I don't want it to come to the point where my warranty gets voided. Not sure on the proper steps to take on it