Don't forget KAM is Keep Alive Memory and may be listed as
a memory power supply or something along those lines.

It is just volatile RAM or volatile memory. If it loosed power
it's gone. Things like PIDs and trans learning are stored there.
There are others. The odometer is not stored there that has to
go into non-volatile RAM so when you pull the B+ you still
have the data.

If anyone has an open PCM please post some photos of it.

Sean

 

Good point Yahiko. I am compileing a post offline trying to explain where I am comeing from. LOL My internet connection is acting flakey again. Just didn't want yall to think I had abandond this.

 

After power has been re-applied and after a period of time the memory should build and clearing the KAM code P0603 should not come back... I would think. But after clearing the code numerous times it comes back every time.

 

In a nut shell that is the point of all this looking.
Some people it does come back others it does not. I am trying to figure out the why.

 

Your not the only one with flakey connection status. Mine went down today
when my little rack with all the warm little boxes got too hot and had a case
of heatstroke. Plug the rack fan back in and cycle the power and I'm Back


Sean

 

Let me explain a little where I am comeing from on the KAM issue.
The information in Keep alive memory can never be permanently lost/deleted from the PCM memory.
It has to be stored somewhere in permenant memory so Kam can be repopulated with information otherwise you truck/car would never start and run again at least to my simple logic and what I actually
remember. I liken it to a temporary memory buffer on a home computer.


Even when you actually changed the battery once you did after a few seconds of key on or cranking the vehicle would start and run. If the Kam did not repopulate with data how else would it be able to do that. Once you cleared the code it would not come back.


On the 6.0 PCM there is no battery but it has to get power somewhere, I am trying to find out where and how.
I have read many post where they have had the code since day 1 and it never stays cleared and others do not experience this problem. Again why and how? Once power is restored after a few seconds the code can be cleared and the vehicle starts and runs and the code never comes back.


These are the questions I am trying to find the answer to.

 

Come on guy don't quit now there are good minds on here and some good points and ideas given.
Altho without actualy opening one up or finding a wire diagram of the pcm circuits them selves we may never get an answer. Proprietary info again?

 

Just to continue the conversation, I think of memory buffers as losing what they were thinking about if the power goes away, it "volatile" memory. Ram (random access memory) is the processors work area, sorta like a chalkboard is to a teacher, it's also almost always volatile. If you want to keep these types of memory alive, power must be applied without interruption, that's what you're thinking of I believe.

There are other types of memory chips that don't require power to keep their programming, ROM (read only memory). This type of chip has the programing or software burnt into it. Turn it off and back on and your "stuff" is still there. The draw back is once the software is written to it can't be changed. If you want to change the software you have to change the chip- think OBDI. Or the BIOS of a home computer.

A processor that's at the crossroads of all this info has areas of RAM, ROM, and sometimes a third type of area that can also be a used to remember instructions and values. An EPROM (eraseable programable read only memory). This type of chip won't loose it's memory when the power goes off and the memory can be changed. Pretty cool stuff.

I've opened up a couple of ECM's and never saw a nickel battery like in a home computer. They may be there, I just haven't seen one.

Something else to consider is the PCM has to supply clean power - that is to say if you looked at it on a Oscope it would be a steady, smooth line, to all the sensors. So like the FICM, there's a power section and a logic section. Normally, the power section would supply that same clean power to the processor and memory areas of the PCM as it sends to the sensors. One of the pieces of hardware used to smooth out the power is a capacitor, it can be used to help fill in the dips when the main power goes low for a split second. A cap acts sort of like a battery except it's designed to handle higher voltages and discharges pretty quickly, but it's possible to use the right cap as a battery of sorts.

There's a guy who made a few YouTube videos about sucessfully using very large caps (six of them were about the size of a regular car battery) as a battery for his car.

You probably still have one of those 9v batteries with a cigarette lighter plug thing in your tool box. If the PCM had a battery, or was using caps as I was speculating about, we wouldn't need those. I'm not sure which makes/models of vehicles require using that thing when changing the battery but several years ago I quit using it much. I like the idea of resetting the memory in the ECM occasionally and forcing it to re-learn. I'll reset the clock and radio stations as a trade off. Last time I used it was because my buddy told me of a warning on the alarm system on his truck.

Sorry for rambling again

 

If your rambleing we both are because that was the thinking I was useing.
Kam would act like a memory buffer temporary storage loos power or close the program buffer clears and is ready to temporarily store new info. Mainly to speed up operation.
But I think you can't permenatly clear KAM memory or you would have no info to restart and run the vehicle. Somewhere that info would have to be stored in permenant memory and then rewritten to volital memory. I am pretty shure or way out in left field again. Maybe I am thinking to linear again LOL
Thinking out loud is all. Just how it does it exactly escapes me for now.

 

P0603 Internal Control Module Keep Alive Memory (KAM) Error
getting close but no map , look to the PCM for details

 

Question on this topic
Just checked for DTCs on the edge and it's coming back with
P0603 internal control mod Kam error
P1000 monitors check not complete-more driving required.

Is this normal with it being tuned?
I'm not reseting everytime I turn off the key am i?

 

it looks to be the # 40 Kapwr wire for power .

 

Here is an odd answer to you question coming from the computer and electronics fields.

The PCM is a basic computer or better yet it is a process control device or PLC.
I think the PCL is closer to what it is.
Anyway You have ram, EPROM and EEPROM (you can reprogram EEPROM).
For the processor section you have the CPU and a little program in the CPU ROM
called a BOOT LOADER. What the boot loader is start by taking the info stored in the
ROM or EEPROM and loads it into the active memory in this case the KAM with a
basic code that is then updated and adjusted to the vehicle it is in. (Relearn process)
But the thing is it only does this on KAM loss or anytime the system has no power.
Like when the batteries are removed. It does not have to take very long if there is not
a large instruction set to load. (The code) Once the data is loaded and the check sun
is verified your ok to start. Fail the check sum and you may still start but with a CEL.

I'll type more after you get done chewing on this part. And I really need to get my
computer glasses fixed. I broke the rim today and the lens won't stay in. Stupid expensive.

I don't think I made any big goofs here. We will see.

Sean

6.0L Tech Folder

 

Thanks guys now we are getting some where.
Rusty the ECU I refer to were the very early production 70 to73. Sometime in late 73 the battery acces cover was removed and the ecu was sealed at least the ones I remember. Great info as well. The9v battery minder I haven't used since 1990 LOL they only worked for a few hours and were mainly for keeping your clock alive and your radio programed with your station selections IIRC.

04bradford thank you that confirms and clarifies what I suspected Kam to be a working memory buffer. However on the systems I have worked on that had the KAM problem. I checked wireing suspecting that as a possible culprit many times. I came to the conclusion that it may be internal to the PCM itself. #40 has always had stabil power when tested at the plug.

Yahiko great info as useuall. What else can I say other than you wana help me find my hacker??? LOL

Thank you all keep them comeing

 

No Problem Danny boy , don't forget the Ground will play a role in power loss in a circuitry, On the Boards ,capacitors , little micro chips that hold enough power to hold Memory for certain things , it's crazy and will make you pull your hair out. or better yet this is a good topic of what Kam really is