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

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Idriveaho

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the tpms light is flashing? I don't think it's supposed to do that

I didn’t think so either. So left work start it up doing same thing. Front right shows 2 dashes. Let it run for a minute before I take off. I start hearing a horn go off like in Morse code. I’m thinking who the hell is doing that. Then I open my door and realize it’s me. Damn thing was going crazy with the horn. Turned it off and started up again, all is back to before the horn Tourette’s. Start driving out of the lot into road, blinking stopped and now just lit up. Get on interstate a few miles and now I’m reading tire pressure again.

Here is a pic. Earlier we were talking about voltage, the gauge has been reading 15 volts the whole 30 minute trip. I have a car charger that actually reads voltage. As of right now I’m sitting in it and it’s been shut off and it’s reading 12.1. I have a feeling maybe my battery is doing this. Just like yesterday I had 4wd issue that disappeared. I had it remote start so it’s warmed up a little before I go. Starting to piss me off.

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Doubeleive

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I didn’t think so either. So left work start it up doing same thing. Front right shows 2 dashes. Let it run for a minute before I take off. I start hearing a horn go off like in Morse code. I’m thinking who the hell is doing that. Then I open my door and realize it’s me. Damn thing was going crazy with the horn. Turned it off and started up again, all is back to before the horn Tourette’s. Start driving out of the lot into road, blinking stopped and now just lit up. Get on interstate a few miles and now I’m reading tire pressure again.

Here is a pic. Earlier we were talking about voltage, the gauge has been reading 15 volts the whole 30 minute trip. I have a car charger that actually reads voltage. As of right now I’m sitting in it and it’s been shut off and it’s reading 12.1. I have a feeling maybe my battery is doing this. Just like yesterday I had 4wd issue that disappeared. I had it remote start so it’s warmed up a little before I go. Starting to piss me off.

View attachment 265235
I would have the battery load tested and clean and check your battery cables & grounds, power fluctuations make these trucks do all kinds of weird shit.
i just went thru this with my Silverado, the alternator was sending 18v microamp spikes to the bcm and making the ignition reboot which made the radio, cluster, and a bunch of modules freak out I was getting all kinds of codes and communication problems.
 

Idriveaho

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I would have the battery load tested and clean and check your battery cables & grounds, power fluctuations make these trucks do all kinds of weird shit.
i just went thru this with my Silverado, the alternator was sending 18v microamp spikes to the bcm and making the ignition reboot which made the radio, cluster, and a bunch of modules freak out I was getting all kinds of codes and communication problems.

I’m going to have to have it load tested the battery terminals look clean and tight. Also I went ahead and restarted it in the driveway and the tire light is no longer on...
 

Rocket Man

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I would have the battery load tested and clean and check your battery cables & grounds, power fluctuations make these trucks do all kinds of weird shit.
i just went thru this with my Silverado, the alternator was sending 18v microamp spikes to the bcm and making the ignition reboot which made the radio, cluster, and a bunch of modules freak out I was getting all kinds of codes and communication problems.
Did you get that issue resolved?
 

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Did you get that issue resolved?
ya no more problem after they changed the alternator, it was under warranty so I only had to pay for the diagnostic time because I have a bunch of aftermarket stuff installed.
did you check for continuity on your rear window defroster? if you put a meter on tab to tab it should have continuity, if it doesn't that is why it is not working.
 

Rocket Man

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ya no more problem after they changed the alternator, it was under warranty so I only had to pay for the diagnostic time because I have a bunch of aftermarket stuff installed.
did you check for continuity on your rear window defroster? if you put a meter on tab to tab it should have continuity, if it doesn't that is why it is not working.
Good call. I had checked for voltage at the grid with the switch turned on and had nothing. Both the tabs looked good, they aren’t falling off but the left one isn’t making contact with the grid, there’s zero continuity from that tab to the grid. I’ll either try soldering with silver solder since the tab is solid or buy a Frostfighter kit again.
Edit: I found a Frostfighter grid repair kit in my garage, saw it had a bit of the epoxy left over. So I cleaned up the area and masked off the area around the tab, then used the FF and went to pull off the masking tape and realized I shouldn’t have put tape over the pad itself, only on the glass. It took a big part of the pad but only in the middle, it still had contact areas. Anyway, I dug the last of the epoxy from the bottom of the bottle and painted it over the missing pad area. I hit it with a heat gun for a couple minutes. I’ll wait until tomorrow to see if I have continuity.
 
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