What did you do to your NBS GMT800 Tahoe/Yukon Today?

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Doubeleive

Wes
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Video I saw had the Tech 2 reboot after the starter cranked. Even with the 12vDC cord plugged in, the Tech 2 tries to draw power from from the OBDII port first. As long as there was power detected from the OBDII port, it would not kick over to the 12VDC feed from the other power supply. The switched extender cuts the power coming through the OBDII port, but the rest of the data does its thing. Since the power is cut off from the port, the Tech 2 will run off the 12VDC supply.

This may only be with the clones... Maybe it was only an issue with older clones, that has been since resolved? The video was from 2020. Maybe the problem has been fixed by Vetronix already?

The guy in the video found that his rebooted when initiating the engine cranked over. The switch seemed to solve that. For about $11, i figured it would be good to have if it kept the tTech 2 from rebooting during a diagnostic session that requires starting the engine.

Here was the video...
my 1st guess is the 12v supply they were using was either not enough amperage or was defective or was not plugged into the correct place.
if you look on the tech2 on the bottom edge there is a power port plug, that is where you plug in a 12v dc power supply.
when I plug 12v dc to my clone tech2 in that location it does not reboot or shut off when the key is turned off or when the engine is started. I bought mine around 3 years ago.
 

MassHoe04

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my 1st guess is the 12v supply they were using was either not enough amperage or was defective or was not plugged into the correct place.
if you look on the tech2 on the bottom edge there is a power port plug, that is where you plug in a 12v dc power supply.
when I plug 12v dc to my clone tech2 in that location it does not reboot or shut off when the key is turned off or when the engine is started. I bought mine around 3 years ago.
Thanks! You are probably onto something with this.

The guy in the video had the 12VDC supply was plugged into the port on the cable...

20220215_114631.jpg

Not on the port on the bottom of the head unit...
20220215_114638.jpg

If using the port on the head unit prevents the voltage drop from causing a reboot when the engine cranks, then I might have wasted $11 on the Ebay switched extender.

Maybe mention of this in our discussions will actually save people from thinking they have to buy that cable.

Anybody want to buy an unused switched OBDII extender cable? LOL

Follow-up: Vetronix instruction book says 12VDC "To ensure proper ground, power tester through the DLC power jack, NOT the power jack on the Tech 2". They are referring to the port on the cable for proper ground... However, that is showing the 12V power being fed from the 12V cigarette lighter power cord. Use of the AC to 12VDC power supply would be properly grounded (one would expect) at the wall outlet, so it can feed directly to the power port on the bottom of the Tech 2 device.
 
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tRidiot

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Thanks! You are probably onto something with this.

The guy in the video had the 12VDC supply was plugged into the port on the cable...

View attachment 363289

Not on the port on the bottom of the head unit...
View attachment 363290

If using the port on the head unit prevents the voltage drop from causing a reboot when the engine cranks, then I might have wasted $11 on the Ebay switched extender.

Maybe mention of this in our discussions will actually save people from thinking they have to buy that cable.

Anybody want to buy an unused switched OBDII extender cable? LOL

**** - I just bought one, too. <sigh>
 

Doubeleive

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Thanks! You are probably onto something with this.

The guy in the video had the 12VDC supply was plugged into the port on the cable...

View attachment 363289

Not on the port on the bottom of the head unit...
View attachment 363290

If using the port on the head unit prevents the voltage drop from causing a reboot when the engine cranks, then I might have wasted $11 on the Ebay switched extender.

Maybe mention of this in our discussions will actually save people from thinking they have to buy that cable.

Anybody want to buy an unused switched OBDII extender cable? LOL

Follow-up: Vetronix instruction book says 12VDC "To ensure proper ground, power tester through the DLC power jack, NOT the power jack on the Tech 2". They are referring to the port on the cable for proper ground... However, that is showing the 12V power being fed from the 12V cigarette lighter power cord. Use of the AC to 12VDC power supply would be properly grounded (one would expect) at the wall outlet, so it can feed directly to the power port on the bottom of the Tech 2 device.
that's also assuming a properly working tech2, the clones have the voltage defect, using a dc power supply is a easy work around, you really only need it if you are programming a module or doing a evap test, etc normally just for reading codes or troubleshooting it's no dig deal.
 

Fless

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I am thinking that there is an upgraded power module for inside the Tech 2, too. I don't have time to look for it right now, but I think Dr. Shock may have a video on what to buy and how to replace it. Might be someone else, though.
 

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