Make sure the adapter wiring matches the diagram on the cover of your female plug-in on your truck too.  Some use the center pin for backup lights,  yet others it is an auxiliary.  Also make sure that the lobe on the male is lining up with the lobe on the female plug-in too.

Trailer, one side, brake and turns dont work, same wire, same bulb filament.  Sounds like a ground problem.  With other tow vehicles its ok.  Are these 7 pin to 4s?  Could be the wrong adapter?  Not all 7 to 4 pins are the same.  Sometimes too that bad ground seeks its path through the hitch.  

Wrapping up the ice fishing after tomorrow. I’ve never owned a propane auger before this one and the one I have was bought used. Any storage tips?  

They are probably wired differently. I’ve seen this happen.    Actually I had a brand new 2015 Silverado 2500 diesel issued to me as a company vehicle and had issues galore with the factory wiring and the gooseneck trailer I was pulling. It was the biggest nightmare I’ve ever had and it was all with the factory Chevy wiring and integrated brake controller.   

Not the best time of year to be laying in the cold and slop under a truck tracking down wires but I have done that as well. Sounds like you then need to track down the yellow wire on the truck and see where it may be corroded and shorted somewhere.  

Thanks for the response leech. I purchased an adapter similar to that one with the test lights. Both trailers I tried are almost new and both have LEDS. All work great with Moms SUV and Dads truck. I’m thinking it has to be somthing corroded or a broken wire on the truck end. But figuring that out is out of my reach.

Sounds like it may be a bad harness on the trailer it's self.  Get one of these and test the truck again. If all works it's time to fix or replace the trailer harness. I've done both on the 5 different snowmobile trailers I have had over the years. It could just be a bad corroded or shorted rear light fixture on that one side or a shorted wire on that side.   ATB 16687 Truck Trailer Vehicle Plug Tester 7 Round Blade 4 Pin Wire Light Brake RV Tow  

I know this forum gets very little people now days but maybe someone could help me out. So I purchased my self a new ( to me) 2000 Silverado 1500 back in August. Be mindful this is my first truck/vehicle. So I tow often ( boat, snowmobiles, atvs, kayak). But the guy I bought it from had said all trailer lighting works great. So I didn’t think much of it. Well a few weeks after I bought it I hooked up a trailer to try the lights.... well. All running lights work perfect, but, no drivers side signal or brake light, passenger side brake light and signal work great. I have tried 3 different trailers and have tried them on 2 other vehicles everything works great. So first thought is Check fuses right? So it was in at a Chevy dealer getting some work done so I had them cheak it out. Fuses all look good and they told me all trailer lights work perfect. So I thought well maybe my 7 pin to 4 flat adapter was bad. I bought a new one of those and tried again. I got one with the test lights on it and sure enough all lights worked great UNTIL I hooked up a trailer. When I did this it kicked out the drivers side brake light and signal on the trailer. At this point I’m feed up with this issue and I’m to worried about getting nailed so I only tow a little ways from home. Anyone have any thoughts on what this could be? I was thinking maybe a bad ground on truck? But how would you know? And also this truck has spent it entire life in Florida until last May so this is the first winter in MN. But it shouldn’t matter since I tried the lights back in the end of August. Thanks a lot!

So reviving a dead thread ..


The "park switch" may be the cause of the parasitic draw on some of the console equipped models, 
it's an inexpensive switch that sends a shutdown signal to the BCM. When it goes bad the dash lights do not shut off and it drains the battery. 
Fords fix is to replace the whole shifter assembly at around $650.00, they do not sell just the switch. 
Here is the replacement switch with an more detailed explanation of why it happens.

Its under e bay listing 292931561061