Some LBZ questions...

Mogman

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I am starting another Dmax/Humvee swap, I picked up a 07 LBZ salvage truck with 205K and the drivetrain looks OK.
I am pretty strong in the electrical/electronics field albeit not too much with the GM stuff, but I plan on building my own harness as I plan on using the factory cluster and possibly some other "modules"
I am sure I will have plenty of questions but the first is why am I seeing references to a PCM and a ECM in the schematics, are there two different modules or are they contained in the same housing??
I see class 2 data which appears to all be one wire and simply parallel, the high speed data appears to be both parallel and series I ran into this with my LMM conversion when I had high speed com. issue due to the fact I was not using a glow plug controller.
 

2004LB7

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PCM is for the gasoline engines. Often bundled up with the Diesel as the two share a lot of the same electronics. You'll have to sort through it all to determine what is relevant to you

The recent T80 TCM thread has some good information on the CANBus wiring with these trucks that might answer your question
 
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Mogman

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Thanks, I am having a little trouble deciphering all the information, for example in the high speed data diagrams I see a SGCM, starter/generator control module but cannot find it in the OEM schematics (Alldata) I am sure with some time it will start to clear up in my head as it is just a little differently laid out than I am used to.
Actually it is laid out much differently than I am used to...
 
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Mogman

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Thank you for the help, there is no replacement for experience!!!!
It looks like the LBZ is definitely the way to go, Cruise, manual shift all in the ECM, looks like it would be possible to "trick" the ECM to think that the PTO is on giving high idle also.
A couple questions have come up.
This truck only had the trip switch for DIC operation, this ECM was set up for DSP5 so I will need a tune, is there a difference in tunes between this setup and the one with the DIC switches?

Also can remote start be added? or is that in the BCM?

I see the BCM controls the brake warning light in the LBZ cluster via digital bus, but it simply provides ground in the logic so I can break that out and use the original Humvee parking brake and master cylinder switches, this is going to be cool if I live long enough to get it finished..
It looks like the only thing so far I would like that is in the BCM is tow/haul but I can live without it..

If this goes the way I am thinking I can already see a refit on my LMM Humvee with the original LMM cluster in the future, (will of course need the LMM BCM)
 
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Mogman

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OK so the parking brake must be set for PTO operation, that signal apparently comes from the BCM, a fly in the ointment.
This truck may not get a hydraulic winch so the high idle may not be an issue.
 

2004LB7

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I would suspect the program in the ECM would be different
Maybe. It was found a while back that the turbo brake was still in the programming for the LBZ and all you had to do was wire it up like a Kodiak. GM is pretty lazy when it comes to these things. If they don't need to have custom code they won't
 
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Mogman

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Maybe. It was found a while back that the turbo brake was still in the programming for the LBZ and all you had to do was wire it up like a Kodiak. GM is pretty lazy when it comes to these things. If they don't need to have custom code they won't
I wonder if the Kodiak had a tow/haul mode, which comes out of the BCM on the LBZ, that would be required for turbo brake in the C/K
High idle is not a big priority, cruise and manual shift are and it looks like that will not be a problem with the LBZ.
Heck I might just look for a place to put the BCM in anyway since If I do a re-fit on my LMM truck that would be required to run the cluster.
I am still wondering about remote start, that would be nice because my property fronts on a highway so I don't get the luxury of driving through a neighborhood to warm up the engine and do not like blasting onto the highway with a cold engine, I use it regularly on my 08 3500HD.
I am sure the LMM I am running in the Humvee had it but the LBZ did not come with that option.
 
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Mogman

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On the schematics, I am assuming the wire size given is MM2, that would make the .35 22ga and the .5 20ga and the 8 would actually be 8ga as in the alt charge wire?
 

darkness

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The Kodiak is always in tow/haul, no option. Depending if you wanted to drive around in tow/haul all the time, you could copy the files over to the other tables in the tcm and be in tow/haul and adjust your vane tables for turbo braking.
 

Mogman

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I have a question:
If I use the LBZ, ECM/TCM/TCCM and the cluster which will include the DIC in a stand alone application, what kinds of problems might I have with messages about all the missing modules, BCM, brakes modules etc, etc, etc, there are a ton of "modules" that will no longer be communicating.
With the LMM conversion (that did not use the cluster with its DIC) I have now all I needed to deal with was the items that turned on the MIL and of course the stuff that put me into limp mode.
Is all this addressable in the ECM?? I could of course kill the DIC but that was one of the reasons I wanted to use the cluster.
 

2004LB7

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I'm pretty sure some of those issues are delt with by using a manual transmission OS in the ECM. Then some of the codes are turned off for the rest.
 
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2004LB7

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Can DSP5 be used to create a high idle?

What kind of high idle are you talking about? I haven't looked at a tune in a bit, but if there's an idle table in the dsp segments, then I would say you could... But why not just wire it up for the 'PTO High Idle '?
There is no idle tables in the DSP but if you are careful and increase the torque numbers in the idle area you can get it to Idle higher. Takes some trial and error to get right. You have to be careful with this as it won't idle down if you take off driving and come to a red light. It might try and push through the brakes until you switch it back

Doesn't the LBZ have the high idle switch in the programming and you just need to wire it in?
 
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Mogman

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What kind of high idle are you talking about? I haven't looked at a tune in a bit, but if there's an idle table in the dsp segments, then I would say you could... But why not just wire it up for the 'PTO High Idle '?
I will not have a BCM which gives the parking brake signal that is required for PTO operation in the standard LBZ ECM, not a big deal I was just curious.
 

Cougar281

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I will not have a BCM which gives the parking brake signal that is required for PTO operation in the standard LBZ ECM, not a big deal I was just curious.
Uhm... Pretty sure it's not required. I have my truck wired up for it and never set the parking brake. If memory serves, for mine, I took +12v off the brake pedal switch, ran it through another switch so it could typically be off, and then fed that to the appropriate pin on the ECM. That way, when it's in pto high idle, if the brake is pressed, it cancels it.
 

1FastBrick

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This from the instructions for the BD High Idle kit. Shows the circuit only goes to the ECM.

They only ask you to set the Parking brake when using the feature for safety and not to depress the brake pedal. I am just guessing the signal cancels out the PTO function so its not active if you put it in gear.


LBZ High Idle circuit.png
 
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