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

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Doubeleive

Wes
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mikeyss

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looks right, but where is that ground wire from the alternator bracket going? I ran mine from there to the frame on drivers side.
I assume you ran it to the firewall?
It runs through the RVC sensor then to the negative side. It's how the instructions told me to do it. I still kind of find it odd..
 

Doubeleive

Wes
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It runs through the RVC sensor then to the negative side. It's how the instructions told me to do it. I still kind of find it odd..
I have both battery negatives connected together for the sensor, but the alternator mounting bracket ground that I added just goes to the frame.
I don't think that one has to go thru the sensor, pretty sure the sensor is just for the battery ground, otherwise all grounds would go thru it.
did mechman change the instructions?
 

mikeyss

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I have both battery negatives connected together for the sensor, but the alternator mounting bracket ground that I added just goes to the frame.
I don't think that one has to go thru the sensor, pretty sure the sensor is just for the battery ground, otherwise all grounds would go thru it.
did mechman change the instructions?
I will post a picture of the instructions I have either tomorrow or this weekend so we can compare notes :)

The one thing I remember my instructions saying was to not add a ground to frame. I will definitely snap pics of my instructions for you to see.
 
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mikeyss

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I have both battery negatives connected together for the sensor, but the alternator mounting bracket ground that I added just goes to the frame.
I don't think that one has to go thru the sensor, pretty sure the sensor is just for the battery ground, otherwise all grounds would go thru it.
did mechman change the instructions?
Here is how my instructions look:
IMG20240420144237.jpgIMG20240420144820.jpg
 

mikez71

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Those instructions make logical sense to me, though the factory dual battery setups I have seen in the PPV/SSV section are not wire as such.
The second battery ground goes straight to alternator bracket. I suspect GM didn't put too much thought/care into it.

Regarding the RVC sensor, I don't believe it to be used for anything other than keeping track of amps so it can maintain the battery down to minimal safe levels / minimal charge cycles? Or is there something else it helps with?
 

Doubeleive

Wes
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Those instructions make logical sense to me, though the factory dual battery setups I have seen in the PPV/SSV section are not wire as such.
The second battery ground goes straight to alternator bracket. I suspect GM didn't put too much thought/care into it.

Regarding the RVC sensor, I don't believe it to be used for anything other than keeping track of amps so it can maintain the battery down to minimal safe levels / minimal charge cycles? Or is there something else it helps with?
my alternator is wired to the main battery positive
then the battery posiitive splits to small fuse bracket/link to -vehicle main fuse box, etc
the battery positive also goes to the starter and then from the starter to the 2nd battery positive
main battery negative goes thru the rvc sensor to passenger side head and the litle 8 gauge goes to the passenger side frame
2nd battery negative goes to the main battery negative.
alternator bracket I added a ground to frame
everything works fine. been that way for 4 years now

previous to that I had the 2nd battery grounded to alternator bracket and frame like the early gmt800's only the main battery was connected to the rvc sensor
and both batterys had positive to alternator and starter.
but had a bad battery and while trying to figure out the issue just wired it as above and 2 new battery's and no problems since
 

Grady_Wilson

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Adding additional grounds is never a bad thing.
Extra ground leads have solved many a strange issue in previous vehicles I have owned.
One had a weak grounding point under the battery and the temp gauge would freak out every once in awhile.
Also, the lights would dim with low idle, headlights on, wipers on and defrost blowing going.
All that went away with additional grounding.

On my 2002 Nissan Altima SE, I added a grounding kit not long after I bought it new and it has the original alternator 250k miles later.
Some owners of 3rd gen Altimas had weird things happen like eating MAF sensors or alternators but I have had no such issues.
Only thing I have replaced on that car is, starter at about 200k, fuel rail pressure regulator, one fuel injector and the AC compressor this past summer.

I plan on adding a grounding kit to the Denali in the near future.
 
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