BCM wiring and pin diagram needed?

2012 GMC ACADIA
130,000 MILES • 3 CYL • 4WD • AUTOMATIC
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JESSEBARRICK
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I have a short to ground in my BCM and I can find a layout or pin for my BCM?
Apr 24, 2024 at 10:23 AM
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JACOBANDNICKOLAS
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Hi,

According to my manuals, there are a total of 7 connectors to the body control module. If you look below, I attached all of them. Note that after each connector picture, there is a list identifying the purpose of each connector pin.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Take a look and let me know if it helps.

Take care,

joe

See pics below.
Apr 24, 2024 at 7:40 PM
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JESSEBARRICK
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Thank you. My husband thinks it's one of the grounds it's reading 0 #4 pin 9 just don't know where it goes to check it.
Apr 24, 2024 at 8:07 PM
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JACOBANDNICKOLAS
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Hi,

Pin 9 in connector 4 is grounded to the battery negative. See pic below.

When you say he sees 0, how is he checking for ground? Tell him to try this.

Using a test lamp, connect the alligator clip to the battery positive and then probe pin 9 which should be a ground. If the ground is good, the test lamp will turn on.

Let me know what you find.

Joe

See pic below.
Apr 25, 2024 at 6:59 PM
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JESSEBARRICK
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Yes, he said that's what he did. Sorry not zero he had nothing show up. Which would explain my volts being off and it is saying service battery station. Does it go directly to the battery? So, he can follow it.
Apr 25, 2024 at 7:39 PM
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JACOBANDNICKOLAS
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Hi,

It should. Tell him to remove the battery and check for any damaged wiring harnesses or wires under it. Acid can do a lot of damage. LOL

If there is nothing evident, have him run a jumper wire from the ground to a known good ground to see if that resolves the issue. If it does, then he found the issue and can install a permanent replacement wire.

Let me know.

Joe
Apr 25, 2024 at 8:42 PM
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JESSEBARRICK
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Awesome, he's going to give it a try today. Thank you
Apr 26, 2024 at 3:49 AM
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JACOBANDNICKOLAS
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Hi,

You are very welcome. Let me know how things work out for you. I'm interested in knowing.

Take care,

Joe
Apr 26, 2024 at 8:19 PM
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JESSEBARRICK
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The wire at the battery is saying it's grounded. It clips into another wire and he tested it reads good. We can't find a wire diagram for nothing.
Apr 28, 2024 at 5:45 PM
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JACOBANDNICKOLAS
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Hi,

No problem whatsoever. I attached the wiring schematic for the body computer (BCM) below. I didn't know you needed it.

As far as the pics below, they started as two pages, but I had to cut each page in half to make them readable. I did overlap them. Additionally, I highlighted the ground wire that you have been working with.

Let me know exactly what is happening with the vehicle. We started with needing a pinout, but I never knew what was happening.

I hope this helps.

Take care,

Joe

See pics below.
Apr 28, 2024 at 7:11 PM
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JESSEBARRICK
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Thanks. It started with my fan not working so it started running out but at the same time I noticed my volts were high. So had battery and alternator checked they said both were fine. So, I had someone scan and they said codes b1395 and b1529. Which he said was a bad ground in my module. It's been a big pain I tell ya. So, I appreciate you helping.
Apr 28, 2024 at 7:39 PM
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JACOBANDNICKOLAS
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Hi,

The B1395 is either related to a lighting issue or power seat (see pic 1). As far as the B1529, I attached the diagnostics related code B1529 (remaining pics starting with the second pic below). Note that the code can indicate a low or high voltage issue. It also can be related to a grounding issue.

Let me know if this is something you are comfortable doing. Note: The idea that you saw a high voltage indicator may be related to a short to power and not ground. We may be looking in the wrong place.

Take care,

Joe

See pics below.
Apr 28, 2024 at 7:59 PM
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JESSEBARRICK
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Okay, I will show my husband these tomorrow. It all started with my fan not working yet. I noticed it worked the other day its weird. My volts run at 13 but it's been 15 then after a little bit goes a lttle below 13. I haven't noticed anything else going on. It's getting very annoying. It's my only car and I got 2 kids I take to school so it's hard to just drop off for days. So, we're trying to figure it out and of course it's not easy lol.
Apr 28, 2024 at 8:08 PM
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JESSEBARRICK
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Also, none of my steering buttons work my husband hooked a different radio up over a year ago and this issue just started. Do you think it's related? My antenna went out, so we got another but it's still doing it. I just use I heart radio.
Apr 28, 2024 at 8:31 PM
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JACOBANDNICKOLAS
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Hi,

I do think it is all related to the BCM. The charging should not go above 15v. That is the max I would want to see before things start getting damaged by too much voltage.

By chance, have you been able to complete the diagnostics I attached?

Joe
Apr 29, 2024 at 6:58 PM
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JESSEBARRICK
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Yes, I'm starting to think I'm going to need a new BCM my luck. No, he got home from work too late. I did show him the pictures though so hopefully he can get to it tomorrow. What is the b+? But I did notice my fans working today out of nowhere.
Apr 29, 2024 at 7:26 PM
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JACOBANDNICKOLAS
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Hi,

The B+ simple is used to identify battery voltage. So, when you see that indicator, you should have battery voltage to the wire.

Let me know. It is starting to sound like the BCM has failed internally.

Take care,

Joe
Apr 29, 2024 at 7:46 PM