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chasfm11 · 10-26-2011, 07:25 AM

Quote:

Originally Posted by The Bay I

Chas, I do not have diodes on my system. When checking the lights I didn't have MH lights on and then tested turn signals and so forth. I did them separately. I think I have a ground issue and as you stated I may need to put on a ground wire to the MH chassis and then see if I have turn/brake lights. Also I saw in another post that the roadmaster cable and the blue ox cables are wired differently. I was thinking of disconnecting the plug on the toad and just testing the wires by inserting them into the roadmaster cable plug. Don't know if this will work or not. I really appreciate you and Jim's responses.

It is possible that there are multiple wiring schemes out there. Most of the 4 pin plugs are pretty standard. I was assuming it was a 4 pin plug

Another trick is to use a spare battery and feed it directly into the toad end connector. I hook up two wires to the battery, push one into the ground slot (or around the pin on a 4 pin plug) and then carefully insert the other into the other slots. It won't show you flashing on the turn signals but especially for cars with separate taillights, it shows up which circuit is which. On the standard 1157 type dual filament bulb, it shows which filament is lighting. You cannot hurt anything feeding 12 volts into the wiring unless you bump the leads together.

I should have looked up your actual wiring kit before I posted the first time. I just did that now. With your setup, I'd use an ohm meter to verify the wiring. Here's how.

1. put one ohm meter lead on the toad side of cable on each brake or turn signal wires in turn. Touch the other side to frame ground on the toad (preferably the battery cable connection point) and use the highest scale on your ohm meter to verify no continuity. A pinched wire with just a little ground contact can drive you nuts.
2. with the ohm meter in each of the brake and turn signal inputs to the toad, attach a long wire to the other meter probe and touch the bulb end. You should get good continuity on a low ohm meter scale. Here, I'm looking for a high resistance in the kit wiring or its connecting points. I'd do the same thing for the ground lead.

If your wiring passes both of those tests, it is not a wiring problem, thought it could be a plug difference between the toad and the MH.

Good luck.

The Bay I · 10-26-2011, 11:42 AM

Chas, Thanks for the input I will give it shot and see what happens. I will let you know. Thanks again

nalcon · 10-26-2011, 08:11 PM

Sounds like a bad ground. When testing with a light (tester), you are creating a complete circuit with one end of the tester on the socket and the other to ground. Try attaching the test light to the inside socket post and the other end to the socket frame. That will ensure the ground is good if the tester lights, if not the ground is bad.

phays · 10-26-2011, 08:17 PM

I have the Roadmaster tail light kit on my Jeep Liberty. They may be the cheapest, lowest quality set of sockets that I've ever seen. The portion of the socket with the two contacts for the bottom of the bulb can turn in the socket and you can end up without one, or both, of the contacts for the bulb not in contact with its socket contact. I didn't have a left tail or brake/turn signal and discovered that the the bulb contacts didn't align with the socket properly. After playing around with the orientation of the socket contacts I ended up with what I thought was a properly operating tail light. But, I had the socket portion turned 180 degrees and when the tail lights were on, on the left side it was actually the brake light so when the tail lights were on I didn't have a turn signal.

I don't know if my explanation makes sense but you may have changed the orientation of the contacts as you removed and replaced the bulb as you checked out your problem.

The Bay I · 10-27-2011, 03:20 AM

Nalcon, I will check this out this weekend. I'm going camping with a group that we have 3 electricians in it and should be able to troubleshoot it & fix it this weekend, I hope.

Phays, I never thought about the socket not aligning, never had that happen to me but stranger things have happened. Thanks all.

Elkhartjim · 10-27-2011, 05:37 AM

John, if all else fails have them hook you up to 220. That should insure good ground as most stuff will be welded.

I'm joking of course. I hope between four of you you will resolve the problem.

The Bay I · 10-31-2011, 03:50 AM

Well we got it

. It was the taillight converter. Hooked up a spare battery to toad lights and got them to work. Then started troubleshooting on the MH. Best voltage we could get was 5 volts. Finally jumpered in to the wiring before the converter and started getting everything but brake lights. Bought new converter and everything works great.

Thanks for all the responses and the troubleshooting tips. Did I mention electrical isn't my favorite thing

. Thanks again this is a great forum.

chasfm11 · 10-31-2011, 06:22 AM

I'm glad that the spare battery technique worked for you, John. I'm a big fan of the "divide and conquer" style of troubleshooting.

I had a similar situation to yours just after I got my first toad back from the shop. I was pressed for time and let them put the electrical wiring on it when they mounted the base plate. The lights didn't work at all correctly. I happened to have a full sized van with a 4 pin plug on it so I plugged the toad into it and all of the toad lights worked correctly. I didn't understand tail light converters then so I took the MH back to the place where we bought it (we had it less than 2 weeks) and asked for their help. Yep - bad converter box.

Since then, I've put on my own base plates and wiring. Since our Vue has separate bulbs for turn and brake, I bypassed the converter on the MH and set up the toad wires to run directly as the MH does, with separate circuits. My 7 pin connectors are unique because I also run the feed back line for my toad aux brake through them but I don't expect anyone else to plug into them so it doesn't matter.

Elkhartjim · 10-31-2011, 06:43 AM

Good news....whats a converter?

The Bay I · 10-31-2011, 09:08 AM

Jim, Here's a link to a tail light converter. It adjusts the voltage so that the brake lights and tail lights work together. Kind of like having diodes in a box, I believe.

NAPA AUTO PARTS

Gma-n-Gpa · 10-31-2011, 10:42 AM

I may be in left field (lately spent a bunch of time there),but when you use the tester is it pulling the same amount of current as the bulb? If i remember my tester has a lot smaller bulb. I am curious if the problem only shows when there is a "normal" current draw.. if so i would start looking at the ground between Toad and MH. Just my $.02

The Bay I · 11-01-2011, 06:00 AM

Gma-n-Gpa, I was using a multitester and not a tester with a light bulb. I was measuring the voltage at the tail light of the MH and then testing at the hitch of the MH which showed the same low voltage until we replaced the tail light converter.

chasfm11 · 11-01-2011, 07:40 AM

Quote:

Originally Posted by The Bay I

Gma-n-Gpa, I was using a multitester and not a tester with a light bulb. I was measuring the voltage at the tail light of the MH and then testing at the hitch of the MH which showed the same low voltage until we replaced the tail light converter.

This is a situation where using the probe type light like I normally do can get me into trouble. The problem with multimeters is that they don't respond well to flashing lights so I prefer to see bulbs that flash rather than a number roll (digital multimeter) or needles that deflect (analog meters). If you don't pick up on the fact that the probe's bulb is dim, you miss the voltage drop.

I actually enjoy troubleshooting lights. I've worked on lots of sailboat trailers and they can be a real challenge, mostly because of bad grounds. A couple of times, I got so frustrated that I ran separate ground lines rather than trying to use the frame ground and risk bad contact with it. Dunking the lights and their connectors into the water constantly does nothing to improve ground continuity. The metal in the trailer seems to rust around the ground screws, no matter how carefully I coat them.

HD4Mark · 11-03-2011, 09:11 AM

Here is what we went through trying to leave to go south last Sunday. Hook up toad and test lights. Turn, brake and four ways good, no tail lights. Darn (or something like that). Get out my little LED tester and plug it in the 5' extension coming from the RV, good. Next unhook, reattach car battery and try tail lights, good. Hmmm tape splice in wiring just inside grill, undo brown wire (tail lights) and test, 12V. Trace out further and find for the first time the diodes tucked away in the back behind a panel, 12V. This makes no sense.

Next step is to get the magnetic trailer lights out and try them. Plug into the 7 way to 4 way adapter at the rear of the RV and no tail lights, darn again, we just went through a lot of crap and the problem is at the RV. Dig out the spare adapter from the garage and now everything works. Go figure.

I have to figure even though we had 12V all the way the connection was still not good enough to light the lamps.