Unhooked Battery, now it won't start- Please help! *SOLVED*

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Brandon2489

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I believe I recall seeing a tsb about unhooking battery the wrong way and it may damage the bcm. I will see if I can find it.
 

Brandon2489

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Here you go. Looks like what you may have disconnected was a ground path for the BCM.
 

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George B

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I believe I recall seeing a tsb about unhooking battery the wrong way and it may damage the bcm. I will see if I can find it.

Here you go. Looks like what you may have disconnected was a ground path for the BCM.
Good find. I saw that too but wasn’t sure if it applied to the work the OP did. I didn’t look at it much closer.
I guess it comes as a reminder to always disconnect the battery before unplugging modules and such.
 
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Scrapman

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Here you go. Looks like what you may have disconnected was a ground path for the BCM.
According to that tsb, I did it correctly. I removed Only the negative battery cable, and the tsb says to do it first.
 
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Scrapman

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Here you go. Looks like what you may have disconnected was a ground path for the BCM.
ahhh,,, wait. Unless your saying the latch's plug contains a ground for the BCM....Then you hit the nail on the head.

Sadly, I don't have and couldn't find an electrical diagram to figure this out. Towing it to the only mechanic I trust today.
 

CaptainAmerica1

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ahhh,,, wait. Unless your saying the latch's plug contains a ground for the BCM....Then you hit the nail on the head.

Sadly, I don't have and couldn't find an electrical diagram to figure this out. Towing it to the only mechanic I trust today.
This is what did it
 

Brandon2489

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ahhh,,, wait. Unless your saying the latch's plug contains a ground for the BCM....Then you hit the nail on the head.

Sadly, I don't have and couldn't find an electrical diagram to figure this out. Towing it to the only mechanic I trust today.
Correct. The part you replaced contained a body path ground to the BCM.
 

BG1988

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Good find. I saw that too but wasn’t sure if it applied to the work the OP did. I didn’t look at it much closer.
I guess it comes as a reminder to always disconnect the battery before unplugging modules and such.
and you still gotta wait a few min to drain the capacitors which can still short out stuff
 

DougAMiller

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I believe people are told to disconnect the negative to reduce the chance of sparks, shorts, etc. while disconnecting.

From a DC theory point of view, you need both sides to make a circuit.

Do you have a liftgate power switch on the console? And if so, have you tried turning it off?
The reason to disconnect the negative battery cable first is that if your wrench accidently touches grounded metal you are shorting ground to ground, so no problem. Once the negative cable is off, then removing the positive cable is safe since shorting it to metal doesn't complete the circuit without the negative connected. However, if you disconnect the positive cable first and your wrench grounds against something you have maximum unfused current flow through the wrench which WILL produce lots of sparks, but could potentially weld the wrench in place making it difficult to break the circuit. This could result in fire or even an explosion.

I have an uncle that years ago didn't follow this advice and his wedding ring made connection between the wrench and bare metal. It melted his wedding ring and he ended up with a serious burn. So, also another warning, remove rings and watches before working on your vehicle.
 
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wsteele

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The reason to disconnect the negative battery cable first is that if your wrench accidently touches grounded metal you are shorting ground to ground, so no problem. Once the negative cable is off, then removing the positive cable is safe since shorting it to metal doesn't complete the circuit without the negative connected. However, if you disconnect the positive cable first and your wrench grounds against something you have maximum unfused current flow through the wrench which WILL produce lots of sparks, but could potentially weld the wrench in place making it difficult to break the circuit. This could result in fire or even and explosion.

I have an uncle that years ago didn't follow this advice and his wedding ring made connection between the wrench and bare metal. It melted his wedding ring and he ended up with a serious burn. So, also another warning, remove rings and watches before working on your vehicle.
Isn't that what I said?
 

wsteele

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Yep, just trying to explain further.
OK, just checking.

Kind of a habit for me I guess as I have a friend who has mild Aspergers. He will launch into very lengthly diatribes that basically mirror something I just said, without the benefit of just saying some like, "I agree, ...."

I always have to check to see if he misunderstood the point I just made, or was indeed agreeing with me from the outset and just doing it in his special way.
 

George B

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OK, just checking.

Kind of a habit for me I guess as I have a friend who has mild Aspergers. He will launch into very lengthly diatribes that basically mirror something I just said, without the benefit of just saying some like, "I agree, ...."

I always have to check to see if he misunderstood the point I just made, or was indeed agreeing with me from the outset and just doing it in his special way.
I am like that and it p!sses my wife off when I do it. I don't know if I have a condition of I'm just me.
 

wsteele

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I am like that and it p!sses my wife off when I do it. I don't know if I have a condition of I'm just me.
With my friend, it is pretty pronounced. He is a genuine teddy bear, but unfortunately, people that don’t take the time to get to know him, just think he is a jerk. It is a shame, as he is a super guy, once you get past the superficial personality problems. I think it is the only reason he doesn’t have a wife or girlfriend.
 

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