Bought, wrecked, rebuilding a 2009 LMM

malibu795

misspeelleerr
Apr 28, 2007
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Well, been playing around with the thermal scanner.. outside the battery posts being warm haven't been able to find the short ground. Yet.
Started it, checked grounds on block and frame less than 5° above ambient. Which is mid 30s.
😒
Left batteries connected and hooked charger to for sustained 40A float charge. Check things again later..
 

2004LB7

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Dec 15, 2010
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Could there be a chance something like the glow plug controller getting stuck on and drawing full amos for too long? I would think one if the mega fuses would blow though.
 

malibu795

misspeelleerr
Apr 28, 2007
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Glow plug module never got warm and glow plug don't cycle, Neither did the intake heater.

The main feed cable got to about 65-70° and just stayed there.

The BCM case got warm, but I forgot to turn the HVAC fan off, so IDK how much of it was from the HVAC or itself.. I've got the ductwork out for easier access to the BCM which blows almost directly on the BCM 🤦🏻‍♂️
 

malibu795

misspeelleerr
Apr 28, 2007
8,454
705
113
42
in the buckeye state
Played around some more with the thermal,
Definitely had some burnt wire smell when I hooked the batteries up,
With key in the run position, ECM/TCM/BCM/MAF/ shift interlock all get warm, like 70° warm in 30° ambient temps
Run/crank relay, and HD/LP relay also get warm.

Does any of the serial data lines run through the fuse block internally? I've heard of the whole thing going bad and creating weird problems.🤔
 

malibu795

misspeelleerr
Apr 28, 2007
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They warp and cause all sorts of odd issues. Little critters can get in there and wreck havoc as well.
Whale shit

I know kinda "chucked" around while it was out.. and it makes senses there is some sort of circuit board inside it.

Need to pick up some small probes to check continuity..

Soo excited at learning things in not interested in🙄🤦🏻‍♂️🤣
 

malibu795

misspeelleerr
Apr 28, 2007
8,454
705
113
42
in the buckeye state
Called around, Hicksville has these for ~130.. local yard is +/+20 of that.. seams there are 2 variations of the diesel version.
Going to order some DMM probe kits to get into the connectors to test circuits easier
 

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2004LB7

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I'm not sure, someone can probably compare the part numbers, but I believe the gasoline Silverado, Sierra, Tahoe, suburban, etc all used the same fuse block. Just populated the fuses differently. I'm seeing those for far less then the "diesel" ones

 
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