Need help diagnosing parasitic drain

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headala

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I have a 2012 Suburban 2WD LT with the 5.3. I've had it regularly be slow to start or require jumping off if sitting for 12-24 hours. Of course nothing is left on or chargers left plugged in.

Basically I've isolated the problem to the "info" fuse in the box on the end of the dash. No other fuses are using much power. When I pull this one the load goes from 380mA to about 12mA. I just don't know what to do next. Is this a board that commonly goes out? Where is it? How do I replace it? What does it control? Thanks for the help folks.


How I got to this point:
I flipped the door latch to simulate closed, and secured the hood latch to simulate it being closed. Locked the truck and armed the alarm. Waited about 2 hours and then put my multimeter inline between the negative battery terminal and lug, set to Amps. It was reading about 380mA. Much too high. I disconnected aftermarket lights, still the same. So I started pulling fuses under the hood. Took a picture first and then started pulling, waiting a few seconds each time to check the meter. Left the fuses out as I went along. Nothing made much of a change except the LBE2 (I think) 60A fuse that goes to the inner box. When I put that one back in so I could check the inner box, the alarm started blaring, etc. Amps shot up so I had to start over. Put back in all the fuses from my pictures, repeated everything except I left in the LBE2 fuse and then moved to the fuse box at the end of the dash. That's when I discovered the culprit being the "INFO" fuse. Please help.
 

swathdiver

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I have a 2012 Suburban 2WD LT with the 5.3. I've had it regularly be slow to start or require jumping off if sitting for 12-24 hours. Of course nothing is left on or chargers left plugged in.

Basically I've isolated the problem to the "info" fuse in the box on the end of the dash. No other fuses are using much power. When I pull this one the load goes from 380mA to about 12mA. I just don't know what to do next. Is this a board that commonly goes out? Where is it? How do I replace it? What does it control? Thanks for the help folks.


How I got to this point:
I flipped the door latch to simulate closed, and secured the hood latch to simulate it being closed. Locked the truck and armed the alarm. Waited about 2 hours and then put my multimeter inline between the negative battery terminal and lug, set to Amps. It was reading about 380mA. Much too high. I disconnected aftermarket lights, still the same. So I started pulling fuses under the hood. Took a picture first and then started pulling, waiting a few seconds each time to check the meter. Left the fuses out as I went along. Nothing made much of a change except the LBE2 (I think) 60A fuse that goes to the inner box. When I put that one back in so I could check the inner box, the alarm started blaring, etc. Amps shot up so I had to start over. Put back in all the fuses from my pictures, repeated everything except I left in the LBE2 fuse and then moved to the fuse box at the end of the dash. That's when I discovered the culprit being the "INFO" fuse. Please help.

Which one in this diagram is info?

upload_2021-4-9_10-55-6.png
 

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headala

headala

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There is another much more suitable way to check for parasitic draw without pulling fuses. Hit this link and pick one of the videos, and Eric O shows how:

https://www.youtube.com/c/SouthMainAutoRepairAvoca/search?query=parasitic

EDIT: and here is where you can find the Voltage Drop Charts for multiple styles of fuses. Be sure to use the chart that matches the fuse package.
https://www.powerprobe-emea.com/ES/knowledge/fuse-voltage-drop-charts/

Thanks for the tip! I did this method first before I did the pulling fuses method. I think it works well but looking up each drop was a bit of a pain. I started doing all the 10A, then all the 25A, etc. but then I lost track of what I'd done and not done. So that's when I went with the pulling fuses method.
 

swathdiver

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It's number 22 on that diagram (same as the diagram in my car); thanks for replying. I would love any input you can give

Well, best I can tell is that your DIC switch has grounded or shorted. If you have a scan tool that can read the BCM codes, you'd probably have a B3567 stored in there with a symptom code telling you which way it failed. It's either the DIC switch or the IPC, Instrument Panel Cluster.
 
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headala

headala

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Well, best I can tell is that your DIC switch has grounded or shorted. If you have a scan tool that can read the BCM codes, you'd probably have a B3567 stored in there with a symptom code telling you which way it failed. It's either the DIC switch or the IPC, Instrument Panel Cluster.

OK cool. I don't have a Tech2 or a scanner that can read the BCM. If I wanted to check the DIC switch, is there a diagram or picture that I can use to find it?
 

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If you let all the modules go to sleep, not many should have ANY draw. On my NBS the auto HVAC head can take 3 or 4 hours to go to sleep. You shouldn't have many to calculate, most should be 0 volts.
 

swathdiver

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OK cool. I don't have a Tech2 or a scanner that can read the BCM. If I wanted to check the DIC switch, is there a diagram or picture that I can use to find it?

It's the vertical row of buttons to the right of the instrument panel. For wiring diagrams, get an online subscription to the shop manual at AllDataDIY. I looked through the one stored on my computer but my eyes are shot and had to quit.
 
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headala

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So I've done some digging and found out some interesting information. Lots of what I found out confirmed what you guys said...inside fuse 22 = info, which is the DIC. But when I pulled the fuse, what I thought was the DIC, was still on. I thought that it referred to the buttons to the right of the cluster, and the display at the bottom of the RPM. I was confused because the buttons still worked and all of the functions of that VFD still worked. So I dug a little deeper.

After running across some wiring diagrams, it looks like the DIC that fuse connects to is the OnStar module, also called the VCIM. Sure enough, the little green light on my mirror is no longer on. I can't find any other functions in the car that are affected, so I think that this is indeed the main culprit. The resting power draw is now about 90mA, which is more than I would like but much less than it was. I'm going to keep digging and post here, but I hope that info helps someone.
 

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