How do you test a trailer harness with a multimeter?
Beside this, how do you test a trailer bulb?
Use a screwdriver to remove the screws in each corner of the faceplate over the light on the trailer. Unscrew the blown bulb and replace it with one of the same voltage. Test the lights again by pressing on the brakes in your tow vehicle. If the light still doesn't come on, you know there is a problem with the wiring.
Likewise, how do you test the ground on a trailer wiring?
Check out the white wire on the trailer to see if it's actually used as a ground (which it should be). Those 4 wires should be green, yellow,brown and white. Check out the white wire on the trailer to see if it's actually used as a ground (which it should be).
Step by Step
- Using a battery or jump box, connect one end of the black test lead to the negative terminal and the other end to the “Ground” pin.
- Connect the second test lead to the positive terminal of the battery or jump box.
- Make contact with the alligator clip to the “Left Turn/Stop” pin.