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

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Wes
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Typically flickering headlights is a bad ground if not the battery, try adding a ground to each of the headlights and see if the issue goes away, the early Tahoe's are more prone to this from what I have read
 

Hi-psi

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I know I'm all over the place the last couple of days... Haha..

Some continued updates...

My scanner does show the steering position sensor data stream. With my wheel centered, reads dead on 0 or maybe -0.98 to 0.98, either way, good. Full lock to either side reads similar -570'ish to +570'ish, no weird breaks or jumpyness while going through the range of motion.

Onto the electrical issue. I'm starting to lean away from the alternator. Static battery tests good with a voltmeter, started and charging is a good 14.2 or so. What I'm starting to lean more towards now is a bad negative cable. It's tight, and no terminal corrosion, but there's about a 1/4 in gap between the insulation and terminal and although I don't see any corrosion, it does seem to have a little bit of that greenish look to it. From doing some reading, it seems the negative cables going bad are fairly common on the GMT900's and often still appear to be fine on the outside.

When I went to start it just an hour or so ago to test the alternator charge with a voltmeter, it started, but just for a split second acted like it was about to do the total electrical blip thing again. So, I'm thinking that's my first course of action right now is replacing the negative cable, which is relatively inexpensive.
 

swathdiver

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I probably wont ever use them to be honest, I just hate how the stock ones look

There are the plain black ones, then the Denalis and Escalades and LTZ have the fixed boards with chrome trim and there are others that are tubular in style.



In Today's Episode of How The Yukon Wheel Turns... :p

This morning on the way to work, I disabled the Traction Control & Stablitrak (by holding the button down for like 10 seconds to turn both off) and aside from the Traction Control light being constantly illuminated (as expected) it drove perfect.

I'm going to poke around my scan tool

...GM regulated voltage charging system ...very quick flicker/dimming

Flickering with RVC in my experience is when the battery gets weak. Or said another way, as the battery ages and weakens, the flickering becomes more noticeable and can go on for some time before the battery finally fails to do its job. It was 100 degrees out the other day and my RVC had the alternator near shut down so while running, had the kids fire up the Tech-2 (it was still connected) and saw that the battery temp was over 108 or 116 degrees, can't remember. This is an AC Delco Silver that is now 35 months old. I'm thinking the end is near for it.

Can your scan tool look at Chassis (Brake and ABS codes) and BCM codes?

Did you happen to change tires or tire sizes? There's a place in the RCDLR module to tell the computer what kind of tires you're running and at what air pressure so that (I speculate) the ABS/StabiliTrak can adjust for it. If you changed the size, I "think" this needs to be programmed as I've seen no place on GMT900s to change the tire size.
 

swathdiver

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Typically flickering headlights is a bad ground...

What I'm starting to lean more towards now is a bad negative cable.

These two jarred my memory! While only 1 of the 4 had RVC, we've had to replace the negative cable on all 4 of our previous GM vehicles, forgot all about that. Haven't done it on the truck yet. A couple got new positive cables as well. I know a new battery caused the flickering to go away, don't remember if the new cable did too. Good maintenance anyway.
 

Hi-psi

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Flickering with RVC in my experience is when the battery gets weak. Or said another way, as the battery ages and weakens, the flickering becomes more noticeable and can go on for some time before the battery finally fails to do its job.

Battery is less than a year old EverStart Maxx from Walmart.

Can your scan tool look at Chassis (Brake and ABS codes) and BCM codes?

Yes

Did you happen to change tires or tire sizes?

No, stock Denali 20's and OE size.
 

the_behemoth11

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Gave the Tahoe a much needed interior and exterior detailing. Dashboard, gauge cluster and center stack are dusted, vacuumed the carpets and treated the seats with leather conditioner. Exterior was done with the two bucket method as well as a foam cannon wash and spray wax to top it all off [emoji41]

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