Bronco
03-12-2005, 11:28 AM
I need to tow and my trailer lights quit working.
It is NOT my trailer. I have suppled 12 V to the plug and all lights work.
I used a test light at the 7pin on my truck and there is nothing.
I replaced 2 fuses under the hood. TRLPRK 15A and TRLBU 10A.
Still nothing.
Any suggestions?
Max Power
03-12-2005, 11:39 AM
There are a couple more fuses. Could be the ground. Crawl underneath and make sure the wiring is not damaged.
DMAXMO
03-12-2005, 11:42 AM
The 7 pin should be the center pin and is for your back-up lights. The 3 pin supplies your tail or running lights. 5(red) & 6(brn) are your left and right turn/stop respectively. Check these at the truck and see what you have. I am guessing you have a ground problem. Do you have a ground wire through your plug to the trailer frame? This should be on pin 1.
Max Power
03-12-2005, 11:44 AM
Look for rt trlr and lt trlr fuses as well. Should be 10 amp.
Max Power
03-12-2005, 11:46 AM
If you are checking wiring
On the truck:
Green - right
yellow - left
brown - park lights
black - ground
blue - electric brakes
red - power supply
Bronco
03-12-2005, 01:45 PM
Hey guys thanks for the support!
After fiddling with everything for about an hour, I noticed my test light readings were changing?????????
Turns out the metal spades had a very slight layer of corrosion on them. The ones on the truck, 7-4 pin adapter and trailer. So I was not getting a good connection due to corrosion. They have been using alot on magnesium chloride on the roads.
Used some locktite battery cleaner spray. Fixed things right up.
precision37
03-12-2005, 02:26 PM
Go to an auto parts store and get some silicone/dielectric grease and put a dab on all of the contacts. This will help keep corrosion away.