Electrical and lighting problems

Today I brought a truck in for inspection and first thing I do is check the lights. One of the fog lights was not working. So I started looking at the light I saw that the ground was very corroded and bad looking. I disconnect the light from the butt connectors and it had power coming in from the main line. So I know the problem is from the wires coming from the fog light. Two problems the butt connectors that connect the main power supply wires to the fog light wires has croshion and green stuff in it. And the wires had rubbed through the rubber sleeve to help keep water out. I put new butt connectors and heat shrinked the bad wire. Here are some pictures....

Set up 

Main power supply for the fog lights.

 Wires from the main power to the fog light. 

Fixed where the wire rubbed through 

New butt connectors and the light works

I also had a truck come in today because  every time the driver hit the brakes the left turn signal would come on. I had to think about this for couple minutes I had never seen this before. After about 30 minutes of investigation I found that the trailer cords yellow wire had come out of the connector that plugs into the trailer. And because of that the left turn signal would go off when the driver hit the brakes. So I recut the wires replaced the old dirty plug with a new one and the problem was fixed.