Electrical issue with new install

[Scooter720]

Hi, I just installed a new custom stereo system in my 2002 Tahoe and I have electrical issues now. Headlights and interior light flickering and I hear relay buzzing in dash. Dash gauges freaking out. Radio turns on then shuts off infinite loop trying to power up. Even when I disconnect all of it still does it. I think I may have damaged the BCM. Truck starts up runs fine though. Has two amps, one for the crossovers and one for the sub. Running 1/0 gauge wire to both power and ground using distribution blocks and 100A fuse at the amps all under rear seat and 250A at the under hood battery. I connected everything perfectly to the best of my knowledge. Not sure what's happening here. Please help. Getting only 7.5 volts to the amps and battery is at 12.6v, with alternator running 14.1v.

CT Sounds Meso 6.5” 500 Watt 3-Way Speaker Set​

CT Sounds ATv2-125.4D 4-Channel 800-Watt Amp​

CT Sounds ATv2-1400.1d 1800 Watt Amp​

BOSS Audio Systems BCPA10RC Head Unit​

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[1aespinoza 10+ year member]

Getting only 7.5 volts to the amps and battery is at 12.6v, with alternator running 14.1v.

With that many things going bad at the same time I am going to say it is a ground issue. You may have left a ground loose.

 

[Scooter720]

With that many things going bad at the same time I am going to say it is a ground issue. You may have left a ground loose.

I have the ground installed onto the rear seat mounting bolt. Is that a good spot? It's soldered tight and crimped really good. I will check other grounds. Thanks for the reply.

 

[HardofWhoring]

8ga or bigger I just crimp with a hydraulic crimper. No need to solder. If you did that first, you might have created a gap that is not being crimped well, (long shot, but can't see the work).

No it's not a good ground. There's a few problems with it. The common wives tale that goes with that bolt, is that "just remove the paint from under the bolt". The problem with that is the entire seat frame is painted and so is the floor. If you didn't remove the paint from those three places, then your ground is going through the bolt, through the sheet metal of the body, through the factory grounding straps (along with all the rest of your vehicle) to chassis. Even if you do it still just skips the bolt. Many people will tell you it works, but ask them how many watts/amps they have.

The best thing to do is post pictures of everything. We might see something that stands out.


The only thing that could cause all of that to go nuts is either a bad ground, or a CL 2 Serial data. Every sensor under the hood goes to a module. Every module sends a good or bad voltage signal through the CL 2 serial data circuits. There are two things that should be able to prove that. Connect to your OBD port and run a test. If it won't even read them, and freezes without completing the original boot test, then it is your CL 2.
I think you also have three cigarette lighters, (I know the pickups do). Two of the lighters are on one circuit, and the third is on a different circuit, (not sure which ones when mounted). In the under hood fuse panel, there are two different fuses for those two different circuits. One is an accessory fuse, (which I think is for one of the cig lighters), and I want to say the other two are on a 15a cigar fuse. The 15a cigar fuse is also for your OBD port. (Or again, at least on the pickup trucks).

If you can run a successful code test when it's going silly, it is a bad ground.

 

[1aespinoza 10+ year member]

I have the ground installed onto the rear seat mounting bolt. Is that a good spot? It's soldered tight and crimped really good. I will check other grounds. Thanks for the reply.

I am thinking more of an OEM grounding for a BCM. As HardofWhoring pointed out, a ground strap or groundind point along the firewall or fenders.

 

[metalheadjoe 10+ year member]

100a fuse for a 1400w amp is way undersized. Obviously not the cause of all your problems, but worth noting.

 

[Scooter720]

100a fuse for a 1400w amp is way undersized. Obviously not the cause of all your problems, but worth noting.

It was the smallest I could find in the Installgear brand that uses the 1/0 gauge.

8ga or bigger I just crimp with a hydraulic crimper. No need to solder. If you did that first, you might have created a gap that is not being crimped well, (long shot, but can't see the work).

No it's not a good ground. There's a few problems with it. The common wives tale that goes with that bolt, is that "just remove the paint from under the bolt". The problem with that is the entire seat frame is painted and so is the floor. If you didn't remove the paint from those three places, then your ground is going through the bolt, through the sheet metal of the body, through the factory grounding straps (along with all the rest of your vehicle) to chassis. Even if you do it still just skips the bolt. Many people will tell you it works, but ask them how many watts/amps they have.

The best thing to do is post pictures of everything. We might see something that stands out.


The only thing that could cause all of that to go nuts is either a bad ground, or a CL 2 Serial data. Every sensor under the hood goes to a module. Every module sends a good or bad voltage signal through the CL 2 serial data circuits. There are two things that should be able to prove that. Connect to your OBD port and run a test. If it won't even read them, and freezes without completing the original boot test, then it is your CL 2.
I think you also have three cigarette lighters, (I know the pickups do). Two of the lighters are on one circuit, and the third is on a different circuit, (not sure which ones when mounted). In the under hood fuse panel, there are two different fuses for those two different circuits. One is an accessory fuse, (which I think is for one of the cig lighters), and I want to say the other two are on a 15a cigar fuse. The 15a cigar fuse is also for your OBD port. (Or again, at least on the pickup trucks).

If you can run a successful code test when it's going silly, it is a bad ground.

When researching this issue, people are talking about the big 3 which I have not done yet. You think it's something I should also do? I will runs the tests and take pics like you said. Thanks for the post.

I am thinking more of an OEM grounding for a BCM. As HardofWhoring pointed out, a ground strap or groundind point along the firewall or fenders.

I will check that out. Thanks

 

[Scooter720]

Okay this morning I found the cylinder head to body ground strap disconnected. The engine was replaced and I guess they did not put that back on so I bolted it back to the head. The BCM seems to be working okay this morning too. I connected just head unit and it seems to be working okay when going through the menus. I haven't hooked up power to the amp until after checking the grounds and upgrading the big 3. I will post the pics I took as soon as I receive them in my email. Appreciate the help guy's.

 

[HardofWhoring]

Your fused distribution block should have each circuit fused at what the amp is or higher, and the wire going to the amp from the block needs to be capable of handing more than the larger of the two fuses.

Your main power wire should be fused as close to or at the battery. That fuse rating should be at or more than the combined fuse ratings of all amps.

The main power wire needs to be capable of handling more than the inline fuse near the battery.

 

[Scooter720]

Your fused distribution block should have each circuit fused at what the amp is or higher, and the wire going to the amp from the block needs to be capable of handing more than the larger of the two fuses.

Your main power wire should be fused as close to or at the battery. That fuse rating should be at or more than the combined fuse ratings of all amps.

The main power wire needs to be capable of handling more than the inline fuse near the battery.

The 250A fuse is right next to the battery and all power/ground wiring are 1/0 gauge from battery to amps. My distro boxes are not fused. They are just basic ones. I have an inline 100A fuse for the sub amp.

 

[Scooter720]

Okay I installed the big three and added a body to frame ground underneath too, but when hooking the battery up I get a very loud spark. So I disconnected the sub amp thinking it was that then try again and it doesn't spark as much but everything sounds great except the bass of course. Do I need a separate battery to power both these amps? I'm afraid to hook it back up.

 

[HardofWhoring]

Did you connect it back the right way? Might be juvenile, but how I learned to remember; your battery is energy, just like you have energy. Be positive as much as you can. You disconnect the negative first, and reconnect the negative last.

My guess is you just did it backwards, and just had a quick arc. Disconnect all negative to grounds. Reconnect all your hot wires, and then connect your grounds last.

 

[Scooter720]

Did you connect it back the right way? Might be juvenile, but how I learned to remember; your battery is energy, just like you have energy. Be positive as much as you can. You disconnect the negative first, and reconnect the negative last.

My guess is you just did it backwards, and just had a quick arc. Disconnect all negative to grounds. Reconnect all your hot wires, and then connect your grounds last.

Yes I know about neg first and last and it was the negative cable that sparked on the battery post. Do I need to run two batteries for this setup?

 

[1aespinoza 10+ year member]

then try again and it doesn't spark as much but everything sounds great

A "discharged" amp will make quite a spark. I use a 12v light bulb to "recharge" amps that have been sitting for a bit.

 

[Scooter720]

A "discharged" amp will make quite a spark. I use a 12v light bulb to "recharge" amps that have been sitting for a bit.

So this is normal and I don't need two batteries for this setup?