7 Pin Cable Replacement - SOLVED

[Boband4]

I have replaced the 7 pin cable on my 2005 Keystone Cougar. There was an awful junction box on the A frame, looked like it was from Home Depot with a cover plate screwed on. I replaced it with a connection box that has a terminal strip with a threaded post for each color wire. I traced all of the colors on the new cord out to the plug using a digital VOM because I had read other posts saying the colors in the new cords didn't line up with the old cord. I did a one for one replacement of connections; I think I have them all reconnected in the same configuration as the old box but I seem to have missed something. I confirmed that I have power and ground in the box (black/white wires) I plugged the cord into the TV and all of the clearance, brake, turn signals work correctly. I can hear the brakes engage when stepping on the brake pedal. I confirmed power from the TV charge line in the box by disconnecting it from and checking for voltage. I reconnected it to the box, unplugged from the TV, and confirmed 12V at the connector. I confirmed the converter is putting out to the battery when plugged into shore power. Problem: I should be able to put a jumper wire or 2 prong flasher in the connector joining the power blade and clearance light blade to activate the clearance lights on the camper (using the flasher is great as a warning if need to park roadside or in a campground without the TV). It isn't working. I tried using a jumper directly from the positive post of the camper battery to the post and wire for clearance lights and that doesn't light them up. Similarly, I ran the jumper from the battery directly to the post for the brakes on the trailer, and couldn't hear the brakes activate. Ohmed out the 2 wires for the breakaway switch. No continuity with the pin in; pull the pin out - continuity between the two. One of them is on the positive post in the connector box, the other goes to the brake post - implication is that if the pin is pulled power should immediately go to the brakes. I cleaned the ground connections between the battery and the A frame. I have coach lights, I have the power tongue jack, I have the water pump working, I have the clearance lights and brakes when hooked to the TV; I just don't seem to have them available without the TV. Anyone have a thought on what I might have missed? Isn't it fun to chase electrical gremlins?

[BurbMan]

CAUTION to anyone else doing this: the pin positions are always the same per the diagram posted but the colors can be different. On mine for example the reverse center pin is yellow and the charge line is red. I also used a VOM to check resistance to confirm what color went to what pin. In my case I was adding additional stop/tail lights on the back of the trailer and couldn't get to the lights on the back wall of the TT.

[westend]

Good deal, Bob, always like to read the happy ending!

[Boband4]

Westend - you were right. It hit me in the middle of the night - When I took out the metal Home Depot style junction box there was a ground wire attached to the box. I mistakenly thought that since the trailer batteries are grounded to the frame and the cord is connected to the batteries that it would make that ground. I ran a white wire from the pin in the connector box to the A-frame and BOOM! the lights work by jumpering across those 2 connections on the 7 pin cable. It just reinforces the age old rule: When you are chasing an electrical problem look at the ground first. Seems like I know the rule, I just failed to use it. Thanks to all for the help. Took me a few days to get back to it, we are still getting rain here in the Northwest. I always want to post when a problem is solved.

[westend]

You have no connection to ground by just power to the RV's pin connections. Connect ground from the RV's trailer pin to ground on the frame or (-) on the battery and then put power to the light pins.

[path1]

MY 2 cents ..

GUESS 1...Undo the screw on socket end and pull back the end and see if you have one or more little strands of wire that got mess up when you slide cover (The plug part) against the end when you finished wiring and are now making conducting elec with terminal next to it. If no strands loose, check other end for same thing.

GUESS 2...Ground on TV

[bobsbbq]

RoyB wrote:
I had to replace my 7-way cable in OFF -ROAD POPUP trailer which also terminated into a standard electric junction box.

I guess I lucked out as the new 7-way cable I ordered from ETRAILER.COM had the same color wires that was inside the electrical junction box. I replaced the wiring COLOR FOR COLOR using twist-on cable connectors.


Roy Ken

I had to do the same thing. I did put new connectors but kept everything else the way it was. Also I took pictures just in case.

[Bob_Landry]

I just replaced the plug. it was marked for the correct colors.

[RoyB]

I had to replace my 7-way cable in OFF -ROAD POPUP trailer which also terminated into a standard electric junction box.

I guess I lucked out as the new 7-way cable I ordered from ETRAILER.COM had the same color wires that was inside the electrical junction box. I replaced the wiring COLOR FOR COLOR using twist-on cable connectors.


Roy Ken

[Boband4]

Yes, crazy part is that this worked when I had the old cable on the trailer, but not with the new one. That implies to me that I missed a connection; but I even put a jumper directly from the battery to the wire for the clearance lights and they didn't come on; but when I plugged into the TV they work correctly.

[Old-Biscuit]

You are placing jumper in the 11 O'clock position (12V Power) and the 1 o'clock position (Trailer lights) on trailer pigtail.....correct?