Bad Ground Found - But What Could Have Caused the Failure ??

DriVer · 05-28-2011, 07:32 PM

I have been having an issue with my toad's auxiliary braking system PLUS the lights on the car were extremely dim. Now this condition only began a very few months ago and I was perplexed about it since I thought that nothing had changed.

I replaced the connector on the car and verified all the connections on the auxiliary brake. That did not help. Later, I had disassembled the umbilical cord caps and made sure all those connections were tight and clean. I used a .22 caliber bore brush to clean the insides of the sockets. Still no improvement. At this point it looks like the motorhome to me.

Determined and having ruled out a couple of items, I started trying to resolve this while I was on the road last weekend on my way up to the Bethpage Camp Resort.

Dim lights and not enough power to bring in the brake - "Classic" - bad ground I was telling myself. I got a few scraps of wire and made a piecemeal grounding wire and I clamped one end on the hitch of the motorhome with a vise grip and I clamped on the other end of the wire to the negative battery terminal.

I asked the DW to man the driver's seat and I walked to the back of the toad. Through the backup monitor I asked her to step on the brake and TaDa! ... Man the tail lights were brilliant.

I opened the car door and backed off on my gain knob on my G-Force controller and lowered it. I asked Col to step on the brake again. No problem the brakes came on just as they were supposed to.

So I raised the knob and set the gain and locked in the knob and that's all I needed to know to resolve this issue once and for all.

The very next day we made our way up to the Pilot at exit 180 in NC and I bought (er borrowed) a set of jumper cables. I clamped one end of the cable to a ground on the coach and the other end to some good grounds under the hood and everything was back in commission.

Once in Bethpage I went to the NAPA and bought 2 mini battery clamps and a roll of #14 wire. I soldered the wire into the clamps and made myself a ground jumper.

On the way home I stopped and returned the jumper cables to the Pilot and got a refund.

The jumper cable that I made worked perfectly for the rest of the trip home. I already have 2 sets of jumper cables at home.

Today I went under the back of the rig and I began to investigate where the grounds are. I saw a white wire that from the Pollock plug to the frame and that looked good and it was tight. There was another white wire that came out of the rail in a wire loom all by itself that went to a welded on 5/16" stud. The location of this stud is behind the generator on the steel framing. I just reached up to check on the wire and no sooner did I touch it, it broke off in my hand.

OK ... I got my stuff and went to work. I got the broken wire and cut back about an inch and half of it or so until I could see good copper. I crimped on a new piece of #14 wire and terminated it onto a yellow ring connector. I removed the screw where the white wire from the Pollock connector was grounded to the frame. I looked through my washer collection and came up with 2 external 1/4" serrated washers. The fastener that I had removed is a #12 Tek screw. I placed one of the serrated washers on the screw and fitted the new wire I had made from the welded bolt. I got the 2nd wire that came from the plug and I was going to put that on but something told me that I should put on a new connector on that wire. I cut the old ring connector off and striped and installed a new yellow ring connector. I put wire #2 on the Tek screw then placed another serrated washer on the bottom of the stack. Tightened on the frame, there's no question that I have a good ground at that location for those 2 wires.

I put on some new wire loom, taped and tie wrapped everything up nice and I expect that I have finally fixed my bad ground condition. I will be able to verify the fix soon since we're are getting back on the road shortly.

One thing that I am not buying is why this wire would have deteriorated since it appears to be is a dry area with plenty of ventilation.

Writing this piece I am going with the possibility that the wire was collaterally damaged by lightning when we were struck back un July of 2008 at the GNR. It is possible. As I was cutting the insulation back the copper appeared to be black but it was solid. This I expect could have been from an over volt (heat) condition that caused the wire to turn color. There have been a few annoying anomalies that have been happening to us since the strike. Hopefully this resolved 1 problem that we had.

The trip to Bethpage was a success by the way. I uploaded 46 pictures to the Photo Gallery which show a good amount of the facility that we will be using for the 11th iRV2 National Rally. See the National Rally topic.

smlranger · 05-29-2011, 05:16 AM

Good detective work and a good find. As many grounds as we have on these coaches, tracking them down and finding broken wires, corroded connections, etc. is a job. Fortunately, I've not yet had problems but there will come a time......

My AF1 is, at times, intermittent or only seems to apply the toad brakes with heavy pedal in the coach. I've not yet crawled around to check things but I betcha it has something to do with a ground.

wa8yxm · 05-29-2011, 11:39 AM

You have copper wire, likely an aluminum "lug" crimped on it and bolted to a steel rail.

That is 3 different metals

Add electrical current and corrosion is GOING to happe, wet, dry, don't matter it is GOING to happen.

And now you know it's happeneing, so you know how to fix it.

Duner · 05-29-2011, 01:05 PM

Quote:

Originally Posted by DriVer

One thing that I am not buying is why this wire would have deteriorated since it appears to be is a dry area with plenty of ventilation.

Writing this piece I am going with the possibility that the wire was collaterally damaged by lightning when we were struck back un July of 2008 at the GNR. It is possible. As I was cutting the insulation back the copper appeared to be black but it was solid. This I expect could have been from an over volt (heat) condition that caused the wire to turn color. There have been a few annoying anomalies that have been happening to us since the strike. Hopefully this resolved 1 problem that we had.

Hey Mike, glad you nailed this one. I vividly remember that lightning strike and how you, Colleen and the dog were still trying to settle down 20 min later. One fellow 2 rows over from you lost his microwave oven.

The thing about a surge hit , be it lightning or static spark, is that it impregnates the equipment with problems and you will never know when the problem gives birth. Keep an eye out for other ground connections that look black and/or sooty and take a wrench to torque on the fastner and a tug on the wires.

Take care buddy,
Bill

PS...This is post 499, do I get another camp fire at 500???

DriVer · 05-29-2011, 02:55 PM

Quote:

Originally Posted by wa8yxm

You have copper wire, likely an aluminum "lug" crimped on it and bolted to a steel rail. And now you know it's happening, so you know how to fix it.

I hear that loud and clear and would agree with you however the old ring was steel, I checked.

DriVer · 05-29-2011, 02:56 PM

Quote:

Originally Posted by Duner

PS...This is post 499, do I get another camp fire at 500???

duner, I believe you do. Let's find out!

My 18,000th post just slipped by my gaze ..... now at 18,002. Dang.

PS: found it

DriVer · 05-29-2011, 07:11 PM

I hooked up the car tonight and turn on the 4 way flasher. Like a fighter jock would say "No Joy!" Lights are still dim.

I therefore resorted to my homemade ground wire and the lights are as bright as the ones on the back of the motorhome.

When I get back, I'll be dismantling/replacing the Pollak plug on the motorhome. That's the only thing that I have not replaced so far.

When I connected the home made jumper, you should have seen the spark that jumped off the clip. There was a lot of current there if you can see tiny sparks.

In the meantime I have my multi meter with me and if I have any time I'm going to test a few things namely going from the ground pin in the Pollak plug to the frame to see if there are 0 ohms.

What's got me stratching my head is that the white wire from the MH Pollak plug is going to a new ground point. If it's not connected or blown out internally in the Pollak plug I would be very surprised.

hamguy · 06-01-2011, 06:43 PM

Quote:

Originally Posted by wa8yxm

You have copper wire, likely an aluminum "lug" crimped on it and bolted to a steel rail.

That is 3 different metals

Add electrical current and corrosion is GOING to happe, wet, dry, don't matter it is GOING to happen.

And now you know it's happeneing, so you know how to fix it.

In all my years, I have never seen an aluminum lug. Tin plated copper is all I have ever seen.

two-niner · 06-02-2011, 04:46 PM

hamguy: Google aluminum lugs and find UL486.

Kerry

SCVJeff · 06-03-2011, 01:56 AM

Quote:

Originally Posted by two-niner

hamguy: Google aluminum lugs and find UL486.

Kerry

I see screw lugs, not crimped

hamguy · 06-03-2011, 10:14 AM

Quote:

Originally Posted by SCVJeff

I see screw lugs, not crimped

I see nothing in that UL486 to treat alum. as better than tin plated copper nor could I find a price comparison. I will bet what the poster saw was the tin plated variety of which I have used many thousands in my 50 years in electronics.

Duner · 06-03-2011, 10:24 AM

Quote:

Originally Posted by SCVJeff

I see screw lugs, not crimped

Ya, there's no ring lugs that are alum. These alum screw lugs are for alum wire, I betcha.

motohomer · 06-03-2011, 11:10 AM

Mike,

If you get a big spark connecting the coach & toad chassis' together, you may have more problems than you think.

depchief · 06-03-2011, 12:04 PM

You refer to getting an arc when you hooked up to the toad. Something is night right. This is not right. We have some checking to do next week. You are getting a cross feed someplace.

Nuge · 06-03-2011, 12:25 PM

Time to put a meter between your clamp on the RV and the ground of the toad? Along those lines, my grandfather, who was an industrial mechanic for U.S. Gypsum and engine mechanic in his garage always told me to put axle grease on my battery connections to help prevent oxidation. Now any suspect or exposed connection on my vehicles gets cleaned and treated with the Triple-Guard grease I've got for my outboard motors. Dielectric insulating grease also works well to keep corrosion from occurring...