B.C.M. Problems

[RevNev]

ECU does not generate BCM codes as you STATED as fact so you are wrong and basically made up bullshit to make a point but got called out for your bullshit as that is exactly what is was MADE UP BULLSHIT trying to make me look stupid

You're doing a good job of making yourself look stupid. Plug an E38 ECM into a VF from a different vehicle, try to start the engine and see what codes are shown. That'll immediately generate a BCM checksum B code fault. There's a few other ECM and PCM issues that'll do the same.

The point is, a B code fault doesn't necessarily mean that a BCM malfunction has generated the fault code.

What you're arguing against is what stooge and I suggested to scan the car with the GM GDS system after confirming efficient battery condition. Instead, because you're a self-proclaimed guru, is not to bother and just fix the BCM you guarantee is the problem. My interpretation of that is a dic*#ead and I hold the trade qualifications to call it.

But now we are down to name calling hey so time to leave it until the OP comes back with the fix and then we will see who is the DH

The dic*#ead bit is your forum diagnosis potentially wasting the OP's time and money without physical diagnosis, that's my issue!

 

[uglyoldfatbastard]

I think that somewhere along the line you have got your wires crossed with how the system works and what I am saying.

The BCM - Body Control Module is the main system for the BODY modules which contain
Immobiliser, IRS, IPC & HVAC just to name a few which all communicate through the BCM as they cannot talk directly to the ECU or the EBCM.

The ECU - Engine Control is self contained and can talk to the BCM, TCM & EBCM etc but not to any of the systems under the BCM - that is plain and simple to understand as the ECU communicates on the CAN bus and the system under the BCM communicate on the GM LAN bus.

The BCM translates the CAN & LAN so it can talk to all systems.

The ECU, EBCM etc do not throw B codes they don't have any to throw HOWEVER they can be the CAUSE of the BCM to throw a B code and that has always been the case.

The IPC does not throw B codes by itself either it reports to the BCM and if the BCM has a DTC that matches the IPC's database for a DIC screen it will record the DTC thrown by the BCM and display the DIC screen.

In the case of putting a ECM from another vehicle in then the B codes are thrown because when the ECU requests persmission to power up systems the BCM ask the immobiliser for the code which it sends to BCM and then requests the same from the ECU which it translates and if they do not match then the BCM throws a B code not the ECU the BCM throws the code and that is because only the BCM can throw B codes.
The wrong ECU is the CAUSE of the B code but it did not throw the B code and that is as simple as anyone can put it.

Multiple codes across multiple systems can be CAUSED by one module failing even though you have multiple system failure codes it does not mean all modules are faulty and can be CAUSED by a broken wire or a failed module and that is when diagnosis takes place except at a Holden dealer they just replace everything.

Now we get down to the fact we understand that the BCM generates B codes for all the modules under the body system control and yes sometimes the IPC records them so it can display a DIC screen and the ECU generates DTC's for the system under it's control and the EBCM does the same for what it controls.

Now the EBCM might generate a DTC that the BCM records because it is in it's database and the IPC see's that DTC and records it as well as it has a DIC screen for that DTC (traction & ABS) we have all seen them.

However all modules in the vehicle are capable of performing a POST ( power on self test)
Modules under the BCM will report to the BCM they have a problem and the BCM will generate a B code for the POST problem for that module. This means that the BCM also does a POST and can generate an internal B code that it has failed somewhere and that is what I am saying about the OP's DTC's from his first post.
Only the BCM can generate B codes and those B codes are internal POST failed B codes.

Now this is a simplistic overview of how the system works but anyone who says a ECU generates B codes has no idea what they are talking about. The ECU can be the CAUSE of the BCM throwing a B code but it the ECU does not throw the B code only the BCM does.

So my statement that only the BCM can throw B codes is factual and correct and if anyone can prove otherwise I want to see that proof as I know it's not possible.

 

[BlackVXGTS]

From the Holden VF Service Manual for you guys to fight over (LOL). Note the code K9 for a Body Control Module in the Control Module References.

On a side note, using the Foxit PDF Reader for searching through the VE/VF PDF manuals for specific items, is unbelievably easier and faster than using the Adobe PDF reader search functions. Give it a try, you won't regret it.

 

[Lex]

using the Foxit PDF Reader for searching through the VE/VF PDF

None of foxit pdf reader or adober reader or any of the other pdf readers would work on any of the pdf workshop manuals.

So l unistalled all of them.

Found Adobe reader 9. Downloaded & installed on my windows 10 pc.
Its never worked so well!

Thanks for the recommendation a few weeks or months ago!

 

[RevNev]

I think that somewhere along the line you have got your wires crossed with how the system works and what I am saying.

I know how the system works and began EFI diagnosis and repair with VK in 1985. In VF over the last 3 years, I've worked at custom programming using the GM SPS and GDS2 system with the genuine Bosch MDI2 to enable features using the VIN's from other cars with the desired features, something the module hackers claim can't be done. My Redline ute is re-programmed with a 340 Maloo VIN enabling the full HSV features then with an ECM and BCM hack to display the correct VIN on a scan tool. My equipment level is extensive aside from the MDI2, I have an Autel and Obdstar system including locksmith level key programming software. There isn't much on a VF that I can't diagnose, repair or modify electronically.

Over the years, I've had so many unsuccessful repairs from people replacing parts and modules that a scan tool identifies to be faulty and doesn't fix the problem, yet they've been charged for it and consequently ripped off by ineffective diagnostics. In relation to this thread and the OP's issue, there are many faults in the VF system with the potential to show the BCM is faulty and responsible when in fact it's not. It's another component, sensor or fault causing the system to trigger a BCM fault that BCM re-programming or replacement won't fix is the point I'm
making.

I've bought in parts at the time I'm sure is the fault and discovered it's not. Talking bullsh*t to charge a customer with components bought in from misdiagnosis is a skill that I've never mastered and is morally wrong. Diagnosing faults properly for everyone is a far better option!

 

[uglyoldfatbastard]

I know how the system works and began EFI diagnosis and repair with VK in 1985. In VF over the last 3 years, I've worked at custom programming using the GM SPS and GDS2 system with the genuine Bosch MDI2 to enable features using the VIN's from other cars with the desired features, something the module hackers claim can't be done. My Redline ute is re-programmed with a 340 Maloo VIN enabling the full HSV features then with an ECM and BCM hack to display the correct VIN on a scan tool. My equipment level is extensive aside from the MDI2, I have an Autel and Obdstar system including locksmith level key programming software. There isn't much on a VF that I can't diagnose, repair or modify electronically.

Over the years, I've had so many unsuccessful repairs from people replacing parts and modules that a scan tool identifies to be faulty and doesn't fix the problem, yet they've been charged for it and consequently ripped off by ineffective diagnostics. In relation to this thread and the OP's issue, there are many faults in the VF system with the potential to show the BCM is faulty and responsible when in fact it's not. It's another component, sensor or fault causing the system to trigger a BCM fault that BCM re-programming or replacement won't fix is the point I'm
making.

I've bought in parts at the time I'm sure is the fault and discovered it's not. Talking bullsh*t to charge a customer with components bought in from misdiagnosis is a skill that I've never mastered and is morally wrong. Diagnosing faults properly for everyone is a far better option!

Once again bragging and no proof to what you claimed about the ECU throwing B codes Hey!
I know how to change vins, program keys, copy all the eeprom data from the ECU and get the immo codes outs and fool SPS2 into programming what I want it to do and none of that is hard in fact I could teach a monkey to do it in half a day.
Also I didn't say you don't know the system if you read the message I wrote I said you have your wires crossed on how the system works and what I am saying. As in you don't understand what I am saying as maybe I don't write as clear as I think.
I don't have any upset customer either and I rip nobody off or charge them like wounded bulls.
You know nothing about me or my history or my knowledge base but you assume I am a hack which is why I have absolutely zero care for any of your claimed expertise.

 

[Immortality]

Come on guys, lets keep it civil.

 

[RevNev]

You know nothing about me or my history or my knowledge base

I'm a qualified motor mechanic with 47 years of experience with a specialty in the VF platform both as an enthusiast and commercially. What's your credentials if you want to get into technical debates with me and expect to be taken seriously?

 

[stooge]

What's this garbage? I've told you more than once and likewise stooge told you too, that other component errors will cause the BCM to show fault codes. The point is, a B code isn't necessarily a BCM malfunction. I showed you a picture of a key programming error causing the BCM to show a fault code, so how's a BCM replacement intended to fix that?

there is no point arguing with him as he does not seem to understand the cause and effect of the system.

he thinks a b code means bcm and nothing else but even the documentation from gm specifies that if the b code was set to do a diagnostic scan on other devices(modules) to ensure that they are not the cause of the code being thrown at the bcm.

i explained this in a previous comment that just because the bcm is the detector of the fault and the module issuing the code it does not mean that the bcm is the faulty module.

as you know many modules in the system have no capacity to throw a code and this is where the main modules are used to detect and throw the code into the system.
you then perform diagnostics on the associated modules.

this is where you find mechanics replacing things that are not faulty because the look at a code and take it on face value then they replace something that is not faulty, the customer pays and they basically start throwing parts at the vehicle until they find it.

 

[RevNev]

there is no point arguing with him as he does not seem to understand the cause and effect of the system.

he thinks a b code means bcm and nothing else but even the documentation from gm specifies that if the b code was set to do a diagnostic scan on other devices(modules) to ensure that they are not the cause of the code being thrown at the bcm.

i explained this in a previous comment that just because the bcm is the detector of the fault and the module issuing the code it does not mean that the bcm is the faulty module.

as you know many modules in the system have no capacity to throw a code and this is where the main modules are used to detect and throw the code into the system.
you then perform diagnostics on the associated modules.

this is where you find mechanics replacing things that are not faulty because the look at a code and take it on face value then they replace something that is not faulty, the customer pays and they basically start throwing parts at the vehicle until they find it.

You're 100% correct stooge!

It's the reason I'd never guarantee a module fault from an error code without a full system diagnosis starting with the battery condition.