What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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mikez71

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A note on charging voltages, doesn't turning tow/haul mode on disable the EPM system?
Oddly enough, mine doesn't seem to bump the voltage in tow/haul mode. Possibly because I changed some settings.
Supposed to happen with headlights on as well but I don't notice it. I usually hit 14.8V after startup, then drop to 13.7V after awhile..

something about 'idle boost' in the wiring diagrams. Haven't every heard of anyone experiencing an idle bump.

EPM.gif
 
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Doubeleive

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Oddly enough, mine doesn't seem to bump the voltage in tow/haul mode. Possibly because I changed some settings.
Supposed to happen with headlights on as well but I don't notice it. I usually hit 14.8V after startup, then drop to 13.7V after awhile..

something about 'idle boost' in the wiring diagrams. Haven't every heard of anyone experiencing an idle bump.

View attachment 424958
that looks like cold weather induced, I have experienced 2nd level many times but don't recall ever having a 3rd level happen, unless it was right at startup for a few seconds
 

Doubeleive

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If anyone has a PN for this, I'd be curious what it look like under and the size. I'd assume the Left and Right is the same, just mirrored.
no they are different, one side is wider than the other, silverado/sierra's have them as well also different....
on the bottom both sides use common metal retention clips used by gm
bottom.jpgbottom1.jpg
 

j91z28d1

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Oddly enough, mine doesn't seem to bump the voltage in tow/haul mode. Possibly because I changed some settings.
Supposed to happen with headlights on as well but I don't notice it. I usually hit 14.8V after startup, then drop to 13.7V after awhile..

something about 'idle boost' in the wiring diagrams. Haven't every heard of anyone experiencing an idle bump.

View attachment 424958


as I understand idle boost from the hpt research I did a while back, it's the ecm being able to raise the idle of the alt can't keep up with the amp load, it can request a higher idle to keep up. the example given was a rainy hot day, full ac running, lights, wipers and all sitting in traffic for long time.

my c6 e38 has it defined in and populated in hpt, but it's not enabled size) since it was a old school 4 pin with a fuse box ref wire, I had hoped enabling it would give me a pwm out out to control the truck one. Sadly it isn't complete, if I command L term in when switched to pwm I would put a pwm out, but not control it and wouldn't turn on without manually doing it. i asked them if a segment swap was possible to add it, but it fell on deaf ears. to old to support to that level.

14.7v for a while after start and then switch down to 13.8 sounds the most correct I've heard for a agm. you might have cracked it.
 

kbuskill

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My first Cold Case Radiator (original design) lasted 2 years/30,000 miles.

Replaced under warranty with 2nd design in 2022, no issues as of yet.

Mine was leaking into the tray under the Radiator as well and appeared to possibly have some cracking around the mounting posts on the bottom and maybe where the tubes met the tank at the bottom, but couldn't verify exactly.

20221102_120819.jpg20221102_120540.jpg20221102_120527.jpg
 

solli5pack

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My first Cold Case Radiator (original design) lasted 2 years/30,000 miles.

Replaced under warranty with 2nd design in 2022, no issues as of yet.

Mine was leaking into the tray under the Radiator as well and appeared to possibly have some cracking around the mounting posts on the bottom and maybe where the tubes met the tank at the bottom, but couldn't verify exactly.

View attachment 425020View attachment 425022View attachment 425023
Is that a petcock valve I see on there for draining the coolant?! Why didn't GM do this?
 

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