Well, still no luck. I did check the area where the looms run together and all wires were good. Of course, this is where the harness disappears behing the fuel tank. I also found the ground, took it off, cleaned it and reattached it with no luck. Short of dropping the fuel tank to see the wires, I dont know what to do from here.

Steve, I double checked those relays, and the wires that come from them run into the same loom. So, when I unplug the connector under the truck, the truck lights go out. So, If I am thinking this thru correctly (Remember, I am not a "wires" guy) Those are for the truck. In my manual, there is no truck turn relay in the fuse box, so is that a possibility? The build sheet I got for my truck says it has the standard trailer wiring package.

So, I feel like I am back to square one again....
I guess I keep pluggin away......

Thanks guys

 

Been awhile since I posted. The relays in question are trailer relays as Steve mentioned. I havent gotten any further as I have not been able to get enough time to drop the fuel tank. I am thinking of buying another wiring harness and using it as a tester, then if it works, thats the issue, if it doesnt, I guess its rewire time.

 

What he said! But it occurs to me that if you open fuse box 4, and pull both of the trailer turn and brake relays out - you can look for a good connection or a short between the relays outputs and the trailer connector at the back of the truck (ON the truck. The trailers are known good units). You may have to unroll a spool of wire to do the test, but you can roll it back up afterward.

Run a wire (unroll - don't cut) from the relay connections to where your seven way or four way is at (sevenway preferred). Bare the tag end of the wire inside the role (if there isn't a tag end you'll just have to cut some wire I guess. Hopefully there is) and use that to connect a meter set on ohms between the end of that wire and the right (or left as the case may be) trailer light connections in the seven way


TRUCK SIDE SEVEN WAY


You want to know if you have:
1) An "open" between the appropriate seven way contact and each relay in turn.

The meter should read close to ZERO ohms. If it's a digital meter you might luck out and it read less than one.

2) You want to know if this wire is shorted to ground.
Do another OHMs check between either the wire or the trailer connector to a solid ground. It should read infinite on any scale...

~If the CHASSIS wire is continuous and not shorted to ground~

3) Does enough volt/amps to drive the lights in a trailer come out?
DISCONNECT TEST WIRE AND REINSTALL RELAYS.
Clip a test light to a good ground near the trailer connector and probe the left and right trailer turn signal connections while the signals are on in the truck. A test light puts enough of a load on the system to give a good indication, it should flash along with the truck turn signals. Fairly bright too, if it's working right. If you have a helper have them put on the brakes during this test.

*The relay sockets should have very tiny connection numbers molded into the bottoms of the sockets. Bottom of the relay may be numbered too.

 

So, Run a wire from the "out" side of relay to the back of trailer connection, or to the wire harness plug that leads to trailer connection?





1. So, If its showing infinite its grounded?

2. So, If I put my multimeter on the L turn wire and touch ground I should see infinite

3. I have done the test light, and the last connection i get any kind of response to is the connection that is under the cab. The multimeter was showing low voltage in the 0.5 - 1.5v range.

I apologize for the questions, but wiring is not my thing. I know just enough to get me in trouble.

 

1) If this test shows "INFINITE" it means there is no connection from front to back - which could be a broken or cut wire. Or a bad connector

2) If this test reads any connection - you have a wire shorted to ground. Which is a bad thing...

3) A meter on this test ought to read 12 solid volts. A test light should light up brightly which shows there is full current flow.

 

Greywolf, I have done both the test light and volt meter on the turns and brakes. I grounded it to a good ground, and there is not enough to light the test light. I have not gotten to the other test yet. I plan on getting back into the garage early next week.

My 6 and 2 yr old dont quite understand why I lay on the floor under the truck yet, and get into other stuff in my garage..

 

I'm suspecting bad or undone connections in the seven way. Possibly broken wires - the relays sound like they work.