Should this be attached to something?

[emt_hound]

Hi Everyone,

I've posted a bunch of pictures over in the photo forum and I'm adding more as I slowly begin rehabbing this old Blazer into something drivable again...but, in a nutshell, here's where I stand right now: 1994 K-5 Blazer with A/T and a 6.5L TD. It was exhibiting PMD failure symptoms before going completely no-start. Batteries are drained and I'm waiting on tools and parts through the agonizingly slow DPO mail system. So far, I've swapped out the fuel and air filters and the lift pump.

Anyway, today I pulled the batteries in preparation for getting a battery tender system in the mail soon. I'm going to try to rehab the batteries since my options for replacement are extremely thin. After I was done, I was just poking around, trying to source an oil leak that's coating part of the engine, and I was distracted by this thin-gauge red cable tied up on the driver's side. It's just hanging out by the windshield wiper fluid and it looks like it should be connected to something.

I took two pictures and I'm attaching them to this post. I'm learning a lot about the 6.5L engine...but I really have no idea what this wire is for. Anybody have an idea?

Thanks in advance!

[JohnC]

Trailer brakes.

[emt_hound]

Really? Golly, that seems so obvious. :) Thanks!

I'm going to display my ignorance again for a second...how does it work? Is it all tucked up in the engine bay to keep it out of the weather and then rolled down the frame when you want to hook up a trailer?

I'm used to just seeing a pin connecter at the hitch.

[JohnC]

I'm used to just seeing a pin connecter at the hitch.

Well, now you know what the other end looks like! It's not hooked up, though. do you have a brake controller?

[DmaxMaverick]

More likely the trailer 12V+ charge/service circuit. The wire is red, whereas the brake wire should be blue. The colors may be incorrect, but the brake control lead shouldn't have a terminal on it (it goes through the firewall to the controller), while the charge lead will (which should connect to a fused power source under the hood at the power distribution box).

[emt_hound]

Interesting...well, I'm pretty sure I don't have a brake controller. Or, at least not one that's obvious. :)

I don't have any wiring at the hitch, but I do have the remnants of an old government radio set up in the cab. Could this have been the power source for the old radio system?

[JohnC]

More likely the trailer 12V+ charge/service circuit. The wire is red, whereas the brake wire should be blue.

Yeah, you're probably right. But, I'm pretty sure when I had to install the whole shebang, before there were factory wiring harnesses, the trailer brake harness was red and brown...

[DaveBr]

I noticed you are low on brake fluid.

[bobt]

On my '93, there were two wires in the engine bay with terminals: a red wire and a blue wire. The red wire was for 12v power to the trailer or whatever you were towing that needed 12v to power it or charge a trailer battery. The blue wire was for the trailer brakes. There was no built in brake controller in my truck and I didn't need it, so I don't know where the blue wire entered and exited the cab. The wires ran along the frame to the back where they were tied up in a bundle along with the wires for the trailer lights. You had to supply your own connector and wire it yourself.
Bob

[emt_hound]

Bobt - If it ever stops raining here today (it's the rainy season), I'm going to trace these wires back from point to point. Hopefully, it'll shed light on the purpose. At least from the answers you guys have given me I am fairly confident that it's not supposed to be attached to anything at the moment. Thanks to all.

DaveBr - I wouldn't say I'm low on brake fluid...I'd say I'm low on a nasty, polluted, water and air contaminated, coffee-like liquid that used to be, perhaps during the late 90s, some form of brake fluid.

The local commissary sells DOT-3 brake fluid in pint-sized bottles...they stock one bottle in their inventory at a time. It's going to be a slow process. :)

[Robyn]

Yesss, factory trailer brake harness/charging etc.

This is a standard issue wire harness if the truck has the factory tow package.

It apears to still be tied off right where the factory installed it.


Missy