T87 Swaps

[kidturbo]

I sorted all the message ID's between an ECM and TCM using recorded LMM and L5P data last night. Made notes on what's shared, what's identical, and what's different. Narrowed the list down to about 6 possible parameters that the TCM could be unhappy about. However I'm using L5P and T87A data as my baseline, since still no luck locating a 16 model.

Then our gas furnace crapped out early this morning, spent two hours on that issue, somehow messed my back up being twisted around, and spent rest of the day sleeping on the couch.. But before all that happend, I did manage to load the gasser version back into the T87, and it seems to have cleared the permanent codes..






Next it's back to the Allison OS, while feeding it all the CANbus messages a typical 2018 4x4 L5P truck would be speaking. Will know if on the right track within the first 11 seconds.. If not, we gonna lean what happens when ya fill up all those CVN history storage buffers..

 

[Cougar281]

Got a few more to go probably lol

Edit: I think it just drops the oldest off the bottom... it appears I've already filled mine up, so flash away.

 

[Cougar281]

Anyone happen to have spare 2016 & 2017 LML ECMs laying around that they wouldn't mind loaning out, even better if it's ok that they get programmed with SPS2?

 

[Woody35]

I have a spare 2016 LML ECM. Bought it used before I figured out how hard it was to flash. Not 100% sure it works but it looks in good condition. PM me an address and I can send it your way.

 

[Cougar281]

I have a spare 2016 LML ECM. Bought it used before I figured out how hard it was to flash. Not 100% sure it works but it looks in good condition. PM me an address and I can send it your way.

Awesome - PM sent - more details in the PM.

 

[kidturbo]

I was out carlot shopping yesterday, and while I couldn't find a 16, I did locate a 19. What took me while to find under the hood, is now mounted on the firewall as far away from engine as they could stick it. Which tells me GM did realize the radiator was bad spot for mounting electronics....

Sent from my SM-S901U using Tapatalk

 

[kidturbo]

While they left the ECM mounting alone on L5P, they did finally color match the rubber baro pressure vent plug.

Always bothered me how the engineers missed that one over the first 15yrs of production..

Sent from my SM-S901U using Tapatalk

 

[2004LB7]

What color was it before? Pink?

 

[kidturbo]

What color was it before? Pink?

Same old black plug Bosch stuck in the FICM, and every other ECU they produced.

Some stylish GM engineer obviously felt same as I did, and demanded a change.. That black plug, just made people ask, what's behind this rubber plug??

 

[Cougar281]

A Package arrived....



And boy the LML ECM is power hungry on key on.. Draws enough to drop voltage enough off my 12v 3A power supply to pizz off my flashscan and make it reboot... HAd to break out my 10A variable power supply to keep everything happy.

 

[Woody35]

Good to hear its working!

 

[1FastBrick]

I was going to say you need at least a 5 amp minimum... 10 Should be plenty...

 

[Cougar281]

I was going to say you need at least a 5 amp minimum... 10 Should be plenty...

For everything else, the 3A is plenty.... The LML ECM, not so much lol. Based on observing the display on the variable power supply, it appears the LML ECM with the T87 peaks at just shy of 3.7A. It's not at that long at all, but just long enough to pizz things off with the voltage drop on the 3A power supply.

 

[1FastBrick]

For everything else, the 3A is plenty.... The LML ECM, not so much lol. Based on observing the display on the variable power supply, it appears the LML ECM with the T87 peaks at just shy of 3.7A. It's not at that long at all, but just long enough to pizz things off with the voltage drop on the 3A power supply.

I forget what my hobby grade one was. But there were issues on some ECU's when trying to Flash. When I bought the new professional version from Bench Force I thought there was 2 versions of power supply at the time now I see only the 5 amp is available.

I haven't had a problem since.

 

[Cougar281]

I forget what my hobby grade one was. But there were issues on some ECU's when trying to Flash. When I bought the new professional version from Bench Force I thought there was 2 versions of power supply at the time now I see only the 5 amp is available.

I haven't had a problem since.

I think it depends on what you're flashing. For the longest time, I was using a 1.5A supply, and recently upgraded to a 3A, and with either one, I was flashing things like Ford EEC-V's, LLY ECM, 5-Speed Allison, 6-speed Allison, nothing crazy, and the 1.5A never gave me issues. Upgrading to the 3A was just 'extra insurance'. But the LML is a different animal. This is the first one that, on the bench, with my V2 connected, on key on, the V2 would reboot like it had been disconnected from the OBD2 port while connected to the PC via USB due to the draw and voltage drop from the OBD2 port. At the end of the day, yeah, 5A minimum is not a bad suggestion at all. Never hurts having more power available than you actually need.

 

[kidturbo]

I run a 7amp Pyramid on the bench for most light weight work. But noted once ya start emulating crank/cam and firing injector solenoids on the LMM, that 7amp couldn't keep up. So I tee in a little 12v sealed backup battery to act as a cap. Works great for short term flashing and testing. But when I started adding nodes and doing the FICM stuff, I grabbed one of the deep cycle marine batteries out of the boat. Now the Pyramid is my 7amp battery charger..

 

[kidturbo]

Well I didn't finish before Thanksgiving dinner was digested, but I did solve it before Christmas at least.. Thanks to some great help from @Cougar281 and whomever graciously loaned him that LML ECM. Time everyone who wants to do a TCM upgrade to head off to the boneyard and grab ya a T87 from whatever you can snatch one out of. OS version doesn't matter.. I should also have first prototype connector in hand by around Jan 1st.

I present you a bench running LMM / T87 combo called Somewhat Happy Camper !!

 

[pl_silverado]

Good job!!

I’m gonna order a new one from gm and have it waiting.

 

[1TRIKHD]

Great work fellas!

 

[Cougar281]

Good job!!

I’m gonna order a new one from gm and have it waiting.

Honestly, I wouldn't bother with a brand new one. Look to car-part.com and there are plenty... 36 pages of them. At the high end, they're insane (2,899, 2,000!?!?!?!?), and a lot are out of touch... Considering you can buy a NEW one from one of the many GM Parts stores online for $175ish, Anything over $100 used, IMO, is nuts, but if you sort by price, there are a bunch that I'd consider 'reasonable' after page 25/26 (at time of posting LOL).