2017 Yukon XL Denali 7.32 amp draw

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I've had this since August. When I got it the seat cooling fans did not work. The dealer had them fixed. A couple of months later I noticed the heated seats did not get hot. The buttons and lights do what they are supposed to but no heat. Then my wife says her door won't unlock. I tried my unlock button and mine would not unlock either. It may have been that way all along because I never use the door buttons. Next was the radio. It would pause like it was going to change to XM or phone, skip a little and go on playing. I left one morning and I got all kinds of messages, Traction control, Trailer brake, Stability, Cruise did not work and probably a couple other things. This lasted a couple of days and disappeared.
At this point I thought it was a wheel sensor and I bought a scanner to check. All the wheel sensors were reading but I had a code for the transmission solenoid I think, at the time, I looked it up and it was behind the valve body. I cleared the codes and no more problems.
Now I get a dead battery quick enough that I unhook the cable if I plan on being parked a couple hours. On the negative cable it reads about 7.3 amps after it settles but it's not sleeping. I did the milli volt test and the radio #29 and AC Inverter #39 in the passenger fuse panel were the highest draws but when I pulled them out I still had 3 amps drawing.
The next highest fuse is in the drivers side dash fuse panel, ICP #39. When I pull it also the draw drops to about 1 amp.
Here's the confusing part. I can put the other 2 fuses back in and the draw remains at 1 amp. I can restart the truck, shut it down and check all the fuses again with the milli volt meter but I can not get it to go below 1 amp by pulling fuses.
The only way I can get the truck to go to sleep is to unhook the harness plug going into the drivers side dash fuse box. It takes about 3 minutes but it will drop in stages to 0.03 amps.
I'm open to suggestions, thoughts, ideas, name calling. I don't care at this point.
This truck is in nice condition, 1 owner before me, no rust and all original.
If you have read this far, thank you.
I will close this out when I have an answer.

 

[Fless]

Agreed, this can be very frustrating.

Tell us a little more about the test setup. Do you have an ammeter inserted in the negative battery cable circuit, or ??

When you test the fuse voltage drop are you reading the fuse test points in millivolts, and using the PowerProbe conversion chart to estimate current draw?

Lastly, have you tested the voltage drop across all of the fuses in the driver's side fuse box?

EDIT: are you using a scanner to check for codes, and one that can read body codes?

 

[Biscuit mobile]

Agreed, this can be very frustrating.

Tell us a little more about the test setup. Do you have an ammeter inserted in the negative battery cable circuit, or ??

When you test the fuse voltage drop are you reading the fuse test points in millivolts, and using the PowerProbe conversion chart to estimate current draw?

Lastly, have you tested the voltage drop across all of the fuses in the driver's side fuse box?

I have a Fluke clamp on amp probe and I'm grabbing both neg cables. I used an in line 10 amp Fluke meter and they were very close in readings. The reading varies slightly all the time when it is drawing over 7 amps.
I am measuring the fuses in millivolts and checking the power probe charts. This last time I did not convert. I just pulled any fuse that wasn't 0.0 millivolts.
I checked under hood drivers side, driver and passenger dash fuse panels and the drivers side fuse panel.
I'm beginning to think it may be something that is one of the bigger closed top max-fuses that is drawing. What will keep the IPC awake? I'm stumped.

 

[Fless]

Ok, that clarifies the setup. I mention it because some of the clamps that will read AC and DC amps don't read accurately at low DC amperages. The ones with the larger jaws aren't accurate for that.

I haven't seen a good way to check the J-case fused circuits except to pull them and insert an ammeter in the socket contacts to complete the circuit.

I added a question to my original post about a scanner.

 

[Biscuit mobile]

Ok, that clarifies the setup. I mention it because some of the clamps that will read AC and DC amps don't read accurately at low DC amperages. The ones with the larger jaws aren't accurate for that.

I haven't seen a good way to check the J-case fused circuits except to pull them and insert an ammeter in the socket contacts to complete the circuit.

I added a question to my original post about a scanner.

Fless, I'm sorry for the delay, but...life. I have an Autel Maxicon MK900 that I'm trying to figure out how to use. If someone knows of a good class or video I'm interested.
After all the testing and battery disconnecting every time I went some where, there were items with codes and some with up to 12 codes. I did a fast delete all and turned everything off. Then I started the car for a minute and shut it off. I hooked the scanner up and I have 2 codes. I don't know if this is enough information but it's what I have for now.
U1526:00 lost com to body control module lost com div line bus
U0121:71 lost com with elect brake control module invalid data

These could apply to the stability trac and trailer control, but could they be keeping the dash display from sleeping?
I will use the Yukon this evening and tomorrow and I'll scan it again. i will have to disconnect the battery overnight or put a charger on it.
I haven't felt this confused since I saw an HEI distributor on a Chevy V8 in 1976.

It says, Lost com to body control module. I see fuses for BCMs 1-8. How many are there and how do I know which one has the problem?
The brake control module code says, Invalid data. Does this indicate that the issue is on the sending end or bad wiring or disregard it?

 

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went to the dealer today. Gave them my notes. Tech was able to run it all down in 2 hours. The draw is due to the IPC and they are on back order with no ETA. The door lock issues are the 2 door lock switches inside. The seat heat is the heater module under the front passenger seat AND the module for the 2nd row seat heaters is bad also. I did not know that. I only have dogs riding in the back, so far.
I'm looking for a new or GM approved rebuilt part # 19435820. This must be programed when installed so they are not plug and play.
They also suggested replacing the negative cable with the 2 leads coming from the battery and the short positive cable because they are known to gain resistance as they age.
If I find and install the IPC I'll update and let you know the results.
The tech today tried reprogramming the ICP an it fixed it for about 500'. They drove it around the building and in front of the service entrance they got to see the info screen do it's thing: Service suspension, Service ABS, Service stability, Service trailer ........... Tech said, "Yup, that's the IPC"