Do as I say, Not as I do

[Ken B]

How long does it take to install two driving lights on the front bumper? Some PO already had something installed there so the +12 volt wiring and
holes for mounting already exist in the front bumper mounts. Simple job right? Well it took 5 hours and the wiring under the dash is not hooked up
yet.

I initially mounted one light and used a couple of alligator clip leads borrowed from a hangar close by. (One light only draws 1.5 amps.) Nothing!
No light. Maybe it is reversed polarity. Tried that. Nothing! I tried the other light. NOTHING! That problem turned out to be an open alligator
clip lead. Not the ends, but somewhere inside the wire itself.

I got another lead and now I have only 2 of the 5 LEDs working in the light. What is this now? I tried the other yet to be installed light. It is
doing the same thing. It looks like a Chinese manufacturing quality problem. Two with same failure. I decided to put a meter across the light. It
was 6 VOLTS under .5 amp load. This dies not make sense. I moved the light to direct across the battery and it works fine. This makes no sense.
Where am I loosing 6 volts? The meter leads read close to 0 ohms. I had been using the chrome bumper as the ground. I moved the negative lead from
the bumper to the frame of the coach. Wow! it now works. The front impact type GMC bumper is NOT grounded. It measures around 12 ohms between the
bumper and the frame it is mounted to with eight 3/8" bolts. I went to the rear bumper and it measures even higher.

So I finally ran the negative leads from the lights to a bolt on the steel frame. Now they work with all 10 LEDs on two fixtures illuminated.

I keep telling people to check the grounds, clean them up, and use the proper ground location. Well, I just got burned by not using the master ground
for the engine system. I chose something that was expedient and got burned. I'll leave it that way for now and if it gives me a problem I will run
ground leads direct to the aluminum plate under the right hood which is connected to the engine master ground.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

 

[Jim Hupy]

Ignore the obvious, that is how we are trained. Sometimes I over think the
obvious to a fault, too. Golly, I hate it when I remind myself to K.I.S.S.
But, at some time our training and experience kick in. You are not likely
to forget that one for a good long time. Thanks for sharing, it might just
help someone else down the line. The car club that I belong to has the
"busted mallet" trophy that we award to the most bone headed stunt
performed by a club member during the year. I so far have avoided being a
recipient of it. (Grin)
Jim Hupy
Salem, Or

> How long does it take to install two driving lights on the front bumper?
> Some PO already had something installed there so the +12 volt wiring and
> holes for mounting already exist in the front bumper mounts. Simple job
> right? Well it took 5 hours and the wiring under the dash is not hooked up
> yet.
>
> I initially mounted one light and used a couple of alligator clip leads
> borrowed from a hangar close by. (One light only draws 1.5 amps.) Nothing!
> No light. Maybe it is reversed polarity. Tried that. Nothing! I tried
> the other light. NOTHING! That problem turned out to be an open alligator
> clip lead. Not the ends, but somewhere inside the wire itself.
>
> I got another lead and now I have only 2 of the 5 LEDs working in the
> light. What is this now? I tried the other yet to be installed light. It
> is
> doing the same thing. It looks like a Chinese manufacturing quality
> problem. Two with same failure. I decided to put a meter across the
> light. It
> was 6 VOLTS under .5 amp load. This dies not make sense. I moved the
> light to direct across the battery and it works fine. This makes no sense.
> Where am I loosing 6 volts? The meter leads read close to 0 ohms. I had
> been using the chrome bumper as the ground. I moved the negative lead from
> the bumper to the frame of the coach. Wow! it now works. The front
> impact type GMC bumper is NOT grounded. It measures around 12 ohms between
> the
> bumper and the frame it is mounted to with eight 3/8" bolts. I went to
> the rear bumper and it measures even higher.
>
> So I finally ran the negative leads from the lights to a bolt on the steel
> frame. Now they work with all 10 LEDs on two fixtures illuminated.
>
> I keep telling people to check the grounds, clean them up, and use the
> proper ground location. Well, I just got burned by not using the master
> ground
> for the engine system. I chose something that was expedient and got
> burned. I'll leave it that way for now and if it gives me a problem I will
> run
> ground leads direct to the aluminum plate under the right hood which is
> connected to the engine master ground.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
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[john r. lebetski]

Since the energy absorbers are paint coated before assembly then charged with oil and nitrogen gas, that's 3 things that sort of don't conduct. I
wonder if anyone ever touched bumpers, then used the pos and neg jumoer cable to make a ling positve, then smoked the energy absorbers when they hit
the key?
--
John Lebetski
Woodstock, IL
77 Eleganza II
Source America First

 

[Ken B]

I had a similar situation on my Colorado pick up when I installed a 7 pin trailer harness / connector. The assembly came with a connector to plug
into the flat 4 pin connector normally supplied by GM for trailers. Then the assembly supplied 4 additional wires. The three that you would expect
and a much heavier ground wire with a big lug on it. Well I hooked the ground to the frame and it did not work. It turns out that GM used the cab
body for ground and there is no electrical connection between the cab body and the frame there is also no electrical connection to the truck bed.
That one also took me a while to figure out.

I have also done the bumper to bumper thing to jump cars. I'm glad I never tried it on my GMC.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

 

[mills]

Ken, I guess I've worked on locomotives too long. Their electrical
system "floats" above the chassis, so I'm used to running ground wires.
So I have to rely on other things to get my "Well, DUH" moments.

> How long does it take to install two driving lights on the front bumper? Some PO already had something installed there so the +12 volt wiring and
> holes for mounting already exist in the front bumper mounts. Simple job right? Well it took 5 hours and the wiring under the dash is not hooked up
> yet.