| Do as I say, Not as I do [message #307264] |
Sat, 17 September 2016 01:53  |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma:
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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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