Trailer and brake controller wiring questions

[TurboDiverArt]

Hi All,

I

[HowieE]

As for the 8 wires. Looks like GM grounds the hitch directly to the frame and shows that wire as the 8th wire on the factory exterior lights drawing.
The wire sre trailer ground white, frame ground black but most likely not in the harness, tail lights brown, LH turn yellow, RH turn dark green, backup light green, battery power red, and auxilary power dark blue.

As for a connector. GM pigtails the lights for a trailer off the connector under the rear bumper. The brake and aux power wires are just above the steering colume forward of the firewall.

I always HARD WIRE any brake control wires and would not rely an a connector. I solder the wires and use larger wireing to prevent voltage reduction over the circuit. Look at my site if you want to see how GM connectors hold up to additional loads.

[TurboDiverArt]

Originally posted by HowieE:
As for the 8 wires. Looks like GM grounds the hitch directly to the frame and shows that wire as the 8th wire on the factory exterior lights drawing.
The wire sre trailer ground white, frame ground black but most likely not in the harness, tail lights brown, LH turn yellow, RH turn dark green, backup light green, battery power red, and auxilary power dark blue.

As for a connector. GM pigtails the lights for a trailer off the connector under the rear bumper. The brake and aux power wires are just above the steering colume forward of the firewall.

I always HARD WIRE any brake control wires and would not rely an a connector. I solder the wires and use larger wireing to prevent voltage reduction over the circuit. Look at my site if you want to see how GM connectors hold up to additional loads. Thanks! I've got no problem hard wiring stuff and bypassing the connector. Knowing the history GM has had with lower than required wires I can't blame you!

Can use the wires incoming from the connector and by-pass the connector or do you suggest running all new wires? If the thick blue wire that's in the back (taped to the orange power wire) is run to the connector in the cab, that one seems strong enough for braking voltage (30 amp?). I think there are 4 wires that are related to a brake controller? Ground, battery power, brake pedal sensor and the trailer brake. Can you just cut off the stock connector and solder and reuse these wires or do you suggest running new ones?

If OK to cut and reuse, what's the color-coding for the stock harness? The trailer I'll be using doesn't have running lights or anything like that, just a standard old open car trailer with 4 round lights in the back.

Thanks,
Art.

[arveetek]

I'm pretty certain that your 99 'burb didn't have a connector for the brake controller under the dash yet. What you probably have is just simply the blue and orange wires running up the firewall under the hood, not connected to anything.

If you'll pop the hood, look down underneath the brake booster. You should be able to see the blue and orange wires taped together in a loop fastened to the firewall. Cut the tape/plastic connector holding the wires to the firewall. The orange wire will have a ring terminal on the end of it which you connect to one of the large studs underneath the black fuse panel on the driver's side fender. There are two studs there that provide a 12 volt positive feed. Each is protected by a large fuse.

The blue wire you have to run into the cab by either drilling a hole and using a grommet, or by punching through an existing grommet in the firewall. Then you'll still have to send a 12 volt positive wire into the cab, tapping off the other stud in the fuse box, and a ground wire. You'll also have to tap into the brake light circuit.

These years of Chevy trucks were sort of pre-wired for brake controllers, but not like the later ones where you just plugged a connector in and you were done.

The connection for the later model trucks is located in the fuse panel on the lower left hand firewall under the dash. You take the black cover off and plug in a harness on the top of the box.

Casey

[TurboDiverArt]

This makes a little more sense. I had asked the Prodigy people because they make a 99-03 harness connector so maybe 99 was the first year for what you describe. What they told me, and until now didn't make sense was:

"It will plug into the left of the driver, on the firewall in the Convenience Center. It goes to upper left corner, second position to right."

I then asked about the connector above the steering column that I thought existed. They responded back:

"It is the Convenience Center. No it is not located above the steering column for GM vehicles. Once you find the Convenience Center it will plug into the upper left corner second position to the right."

Now it makes sense if I understand it correctly from their description and your explanation.

Thanks,
Art.

[arveetek]

Maybe 99 was the first year after all! I couldn't remember for sure.

If so, then yes, it just plugs right into the fuse box. It would be very difficult to hard wire it without the adapter. The GM adapter is very stout and should be a good enough connection. Just plug it in until it snaps.

The Ford trucks use a pigtail w/connector that dangles down below the dash above the transmission hump. The Dodge trucks use the same type of connector, but it's on the left hand side near the emergency brake. On both of those vehicles, you can cut the plug off and hard wire the controller directly to the wires provided by the truck manufacturer. On the later GM's, it's hard to do since it's part of the fuse box.

Casey

[diesel65]

If you read the directions carefully for the Prodigy, it will show you where to pickup the brake light wire on the panel where the chime box is mounted.
This will only apply to the 99 old body style Suburban.

[TurboDiverArt]

Originally posted by diesel65:
If you read the directions carefully for the Prodigy, it will show you where to pickup the brake light wire on the panel where the chime box is mounted.
This will only apply to the 99 old body style Suburban. Thanks. If there is a plug in the "convenience center" for the brake controller, why would I need to find the brake light wire?

[HowieE]

My GM schematic do not show at point on the Con. Center were the output of the brake switch appears. It may be there on the 99s . If you do not find that point to pick up the siganl you can find it in the driver side kick panal were it feeds the center light. There are 2 connector there. The larger has 10 wires and the point you are looking for is the white wire in the corner position K.

[ropinfool]

If you have the new body style burb then all you will need to do is plug in the harness to the convience panel and then wire the 7 way at the back. If you have the old body style then you'll have to do what arveetek says. Either way won't take very long to do. Good Luck. John

[TurboDiverArt]

Thanks guys! I think 200x was the new body style. I thought it strange that Prodigy would list the harness for 1999-2003, who knows, maybe they are wrong. I'll know this weekend when I get a chance to look under.

Art.

[TurboDiverArt]

Hi All,

I took a quick peek under the dash today. I see where the Convenience Center is. A few unused connections but nothing that is labeled. I expected to see something that said Brakes or Trailer or something like that. I think all or most of the connections are labeled like BLK or something like that. Any ideas?

Art.

[arveetek]

I don't believe it is labeled. When looking at the conv. center, the receptacle will be the second position to the right on the top row. It will have 5 pins sticking out, ready to to mate to a 5 pin (six position) connector. If it doesn't look like you have this large of a connection, you probably don't have it.

You might want to trace the orange and blue wires up the frame rail and see if it goes into the cabin at the firewall, or if the two wires are taped up at the firewall. If they're taped up and just hanging there, you don't have the brake controller connection in the conv. center.

Casey

[TurboDiverArt]

Originally posted by arveetek:
I don't believe it is labeled. When looking at the conv. center, the receptacle will be the second position to the right on the top row. It will have 5 pins sticking out, ready to to mate to a 5 pin (six position) connector. If it doesn't look like you have this large of a connection, you probably don't have it.

You might want to trace the orange and blue wires up the frame rail and see if it goes into the cabin at the firewall, or if the two wires are taped up at the firewall. If they're taped up and just hanging there, you don't have the brake controller connection in the conv. center.

Casey I have already traced the wires. Both the Orange and Blue were taped to the firewall below the master cylinder. I did a little more research. It seems that the 1999 pickups had the wiring in the convenience center, the Burbs picked up this wiring in 2000.

Looks like I'll need to do it the old fashion way. The question would be.
With the power lead, should I use a battery lead that is always hot or one that is switched from the ignition?

Thanks,
Art.

[arveetek]

You want a fused power lead that is always hot, so that you can apply the trailer brakes without the key in the ignition, in case of emergency.

[TurboDiverArt]

Originally posted by arveetek:
You want a fused power lead that is always hot, so that you can apply the trailer brakes without the key in the ignition, in case of emergency. That makes perfect sence, thanks!

Art.

[TurboDiverArt]

Originally posted by HowieE:
My GM schematic do not show at point on the Con. Center were the output of the brake switch appears. It may be there on the 99s . If you do not find that point to pick up the siganl you can find it in the driver side kick panal were it feeds the center light. There are 2 connector there. The larger has 10 wires and the point you are looking for is the white wire in the corner position K. Just FYI for anyone else that has a 1999. Howie is correct in that there is a white wire in kick panel. On a 1999, at least a Suburban, there are about 5-6 connections there. It's a PITA. You have to pull the kick panel and pull out ALL the wires from within the body panel. When you pull the kick panel there is a 5" hole between the body panels and tons of wires stuck in there. I looked and started checking connections and was about to give up. In another post someone mentioned a 10-wire connection with a white wire in the corner position "K". That's correct except the 10 wire connector is absolutely the bottom most of the 5-06 connectors. After I had pulled all the wires out and checked connections in vain and was about to give up when I noticed a white 10-wire connector stuffed all the way in the back. Pulled it out and found it to be the only 10-wire connector in the bunch. Checked position "K" and bingo, brake light!

Just wanted anyone else to know that it is there but you have to really dig for it. Gently pull out ALL the wire connectors and look for the bright white connector, it's the only 10-wire one in the bunch. In the corner position "K" is the brake light. I expected the wire to be thicker, it's actually quite thin, probably 18-gauge.

Hope this helps,
Art.