early GMT800 BCM Cloning?

[dubcrazy8392]

my trucks current BCM seems to be having issues and i've been trying to see if there is a way or figure out a way to clone the programming from my BCM to another junkyard BCM. so far i have tried to identify the hardware on the board like the CPU and any 8 pin chips i could locate but it seems GM or delco had someone custom make the hardware or put special batch numbering on them to make them more obscure so its not easily identified for reverse engineering. The images of the chips i posted here are borrowed from another site but are identical to the ones in my BCM's. these are far clearer than what i could get with a cell phone. over all i was trying to determine if this BCM had an external eeprom or if all of the data resided in the within the processor in an internal flash. im trying to avoid dealing with all the nonsense with having to but new hardware, pay the AC delco tax to use their online service and all of that jazz. maybe someone here has dealt with one of these and can shed some light on which direction to go to extract the raw data from this.

[antus]

I'd be looking at those two 8 pins chips as likely eeproms. Can you measure those pin 1 looks like it might go to a small transistor looking power reg or similar, can you check if you have 5v on the top left pin on both of them? and cant see where ground is, on the second one, can you probe out if what pins are connected to ground? are there any chips on the back side of the pcb?

[Gatecrasher]

Check this out. viewtopic.php?t=7034

The CPU looks like it's in the same family as the 04-08 GMT355 BCM. It's probably a custom TI part. Most of the thread is focused on the 09+ TMS370 based BCM, but you might still find something useful in there.

[dubcrazy8392]

I'd be looking at those two 8 pins chips as likely eeproms. Can you measure those pin 1 looks like it might go to a small transistor looking power reg or similar, can you check if you have 5v on the top left pin on both of them? and cant see where ground is, on the second one, can you probe out if what pins are connected to ground? are there any chips on the back side of the pcb?

Im going to make up a bench harness this evening so i can power it on the bench and not have to under the dash with all sorts of equipment. i'll let you know what i find on those chips. as for the back of the board there is nothing other than a few resistors. all the major hardware is on the top.

Made a bench harness and this is what i came up with after probing the pin of each chip with a multimeter. Was thinking and wondering if the same engineers that designed the clusters did this thing too? like one is an eeprom and the other has to do with the serial data like in the GMT800 clusters.

[gmtech825]

did you ever figure this out?

[dubcrazy8392]

did you ever figure this out?

unfortunately i never did figure this out.