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

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Kee Fuller

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Bought new tires about a month ago. Tried to get the hazard certificates from discount tire, but couldn't because they didnt sell the particular brand i bought. A few weeks later my tpms went out. Bout 4 oems on ebay. Discount quote me over the phone 40 bucks a tire to install with road force balance. I finally get in and one of the salesman offers me the certificates. I paid 40 bucks total for the install of the tpms and 100 bucks total for the certificates and it comes with unlimited free road force balances. Paid less than what i expected to pay and got more than expected
 

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Wes
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I was just out in the garage hooking up the Tech2 to reset the trans fluid monitor. I didn't have the engine running, just the key on engine off. The headlights, radio, and HVAC all came on and I turned off the headlights while I stood next to it with the door open and the Tech2 sitting on the seat.

I decided to check for DTCs while I had it hooked up and got 2 for the HVAC system as pictured below. Are these because I had the vehicle on with the engine off and the HVAC still turned on?
7fa678dc8ea41fea9d1ce039c25057d5.jpg
fadadd170171225897441b11ad2f715f.jpg


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no you have a lazy or stuck actuator, now you just need to figure out which one, mine was obvious because the passenger side was blowing warm air when I had it on 60deg
according to the service manual it is either the re-circulation actuator or auxiliary passenger? side, looks like the same code I was getting before I changed my passenger side actuator.
 

Doubeleive

Wes
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there are a couple ways to test it but the manual says to check voltage, I would check both the drivers side and passenger side on full cold with a thermometer, and then switch them to hot and check them again, if the passenger side is a different temp (not as cold or not as hot) then you know, I don't know how you would check re-circulation except visually I think it is on the left side of the airbox under the dash maybe use a flashlight and watch it while commanding and see if it articulates all the way back and forth.

I don't know if you can use the tech2 to command left or right on the front individually I only messed with the rear which is only 2 actuators hot/cold & up/down. to get to the passenger side front actuator you have to do what I did in my youtube video, pull the dash trim off and pull the passenger airbag.
 

swathdiver

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I was just out in the garage hooking up the Tech2 to reset the trans fluid monitor. I didn't have the engine running, just the key on engine off. The headlights, radio, and HVAC all came on and I turned off the headlights while I stood next to it with the door open and the Tech2 sitting on the seat.

I decided to check for DTCs while I had it hooked up and got 2 for the HVAC system as pictured below. Are these because I had the vehicle on with the engine off and the HVAC still turned on?
7fa678dc8ea41fea9d1ce039c25057d5.jpg
fadadd170171225897441b11ad2f715f.jpg


Sent from my SM-G930V using Tapatalk

Your Auxiliary Mode Actuator probably needs replacing. Go into the Body Control Module, HVAC and then Door Positions and see what the commanded and actual states are. If they are off by more than 4 or 5 counts its going to throw a code. The B3782 code makes me think that the thing is wandering, the commanded might be a 32 counts but the actual is all over the place. That's is what my main Mode Door Actuator is doing right now with it's corresponding code like yours. If it doesn't rain tomorrow and my back holds out, it'll get changed.

Good luck trying to order the right one ahead of time. I thought I knew them but was proven wrong! I THINK it is 15-72972/89018375. Already proven that 15-72971/89018365 controls the driver and passenger air temperatures and that 15-73952/89018374 is the main Mode Door up front, it's sitting on my desk.
 

swathdiver

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While on the topic of Tech-2 and AC, do you guys show a reading for Rear Cabin Air Temperature? Mine is blank and wondering if the Aspirator in the headliner is to blame back there. Front gives a reading.
 

wjburken

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about to hit 100,000 soon can't wait tell it says. 99,999 miles

it's sitting at 98800 right now going to get the oil changed on Monday as it's due
Surprised that you’re still not changing you’re own oil after the stories you’ve told about the incompetence of the folks that you’ve been having do it. Besides, didn’t you buy like 5 gallons of Mobil1 last year when they had all the rebates or do you bring your own oil in for them to use?

I’d make sure to double check how tight the filter is.
 

Rocket Man

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Got my Diodes in the mail today, Thanks!!

What gauge wire should I use for this mod?
I used 16 ga and it seems to be ok. I tinned the ends and smashed them flat before I inserted them into the slots in the fuse panel, then carefully rocked the relays in. Be careful not to push too ******* the relays; I found out the hard way when I pushed one of the legs into the relay and it made contact inside. It was no longer a relay but a bridge instead.
 

the_tool_man

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I used 16 ga and it seems to be ok. I tinned the ends and smashed them flat before I inserted them into the slots in the fuse panel, then carefully rocked the relays in. Be careful not to push too ******* the relays; I found out the hard way when I pushed one of the legs into the relay and it made contact inside. It was no longer a relay but a bridge instead.
I wonder how much work it would be to make the connection inside the fuse block somehow? Can you get to the back and solder a jumper there? Wedging a wire into a relay socket would be okay for testing. But I'm not comfortable leaving it like that.
 

Rocket Man

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I wonder how much work it would be to make the connection inside the fuse block somehow? Can you get to the back and solder a jumper there? Wedging a wire into a relay socket would be okay for testing. But I'm not comfortable leaving it like that.
I plan on finding out. I looked online at removing the fuse block and it looks like it plugs into several connectors so I’ll have to figure out which connectors those relays plug into and remove them to gain access under them where the actual wires are. Or possible find the wires outside of the fuse panel by color codes on the schematics but the problem is it looks like the wires go from the outputs of the relays to the fuses which are right next to the relays so I need to connect between the relays and the fuses, not after the fuses. They’re probably just jumpers in those connectors. On another note, I have the same setups in my 02 for 2 mods and they’re been like that for at least 2 years. I kind of like being able to see them. IDK.
 
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Your Auxiliary Mode Actuator probably needs replacing. Go into the Body Control Module, HVAC and then Door Positions and see what the commanded and actual states are. If they are off by more than 4 or 5 counts its going to throw a code. The B3782 code makes me think that the thing is wandering, the commanded might be a 32 counts but the actual is all over the place. That's is what my main Mode Door Actuator is doing right now with it's corresponding code like yours. If it doesn't rain tomorrow and my back holds out, it'll get changed.

Good luck trying to order the right one ahead of time. I thought I knew them but was proven wrong! I THINK it is 15-72972/89018375. Already proven that 15-72971/89018365 controls the driver and passenger air temperatures and that 15-73952/89018374 is the main Mode Door up front, it's sitting on my desk.
Good info. I'm in the car now with the Tech2 hooked up and looking at the door positions. They all seem fine. Attached are the screen shots.

I also notice on the HVAC system data screen that it lists

"Ign. Cycles Since Last DTC" is 100

So who knows. Would doing an actuator recalibration hurt anything?
58b1af59105815c388a97d4d5c3cfc0e.jpg
7a1627bcb4ecca70e6cf70029d5f110e.jpg


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Doubeleive

Wes
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Good info. I'm in the car now with the Tech2 hooked up and looking at the door positions. They all seem fine. Attached are the screen shots.

I also notice on the HVAC system data screen that it lists

"Ign. Cycles Since Last DTC" is 100

So who knows. Would doing an actuator recalibration hurt anything?
58b1af59105815c388a97d4d5c3cfc0e.jpg
7a1627bcb4ecca70e6cf70029d5f110e.jpg


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You can clear them and then run a dtc check again and see if it still comes up if not then check again in a couple days, or clear them and then do a re-calibration and see if it throws a dtc again.
 

swathdiver

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Good info. I'm in the car now with the Tech2 hooked up and looking at the door positions. They all seem fine. Attached are the screen shots.

I also notice on the HVAC system data screen that it lists

"Ign. Cycles Since Last DTC" is 100

So who knows. Would doing an actuator recalibration hurt anything?
58b1af59105815c388a97d4d5c3cfc0e.jpg
7a1627bcb4ecca70e6cf70029d5f110e.jpg


Sent from my SM-G930V using Tapatalk

Looks good, and no, it doesn't hurt anything to do a calibration.
 

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