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How to Fix Headlight Bulb Socket

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  1. step : Inspecting the Socket (0:28)
    • Twist the socket out of the turn signal light
    • Pull the bulb out of the socket
    • Check the socket terminals for green corrosion
  2. step : Testing the Socket (1:15)
    • Turn the ignition to the accessory position
    • Turn on the turn signal with the stalk
    • Raise and support the hood
    • Remove the battery cover
    • Connect a jumper cable to the positive battery terminal
    • Connect the other end of the jumper cable to a test light
    • Touch the test light to a ground point on the frame to check the test light works
    • Touch the test light to the ground terminal in the socket
    • The test light should give steady light
    • If the light is dim or intermittent, clean the terminal or replace the socket
  3. step : Replacing the Socket (3:27)
    • Remove the socket from the electrical connector
    • Connect a new socket to the electrical connector
    • Push the bulb onto the socket
    • Check that the bulb is working
    • Twist the socket into the light
    • Turn off the ignition

Hi. I'm Mike from 1AAuto. We've been selling auto parts for over 30 years!

What's up guys? Here we have a 2001 Ford Focus. We're having some problems with our right side turn signal bulb. We replaced the bulb and it's still not working so we're going to show you how to diagnose it.

This is where the right side turn signal light is that's not working. What we're going to do is we're going to grab the socket and we're going to pull it out, and that's the bulb that we just replaced it with. That's not working, so we'll pull it out.

Something you want to take a look at inside here – it's kind of hard to see, but it you can see that green on the terminals, that's corrosion. That's from the elements, weather getting in there and causing the metals to corrode. So that's going to prevent voltage from getting to your light bulb. So that's one thing.

If this light did not have that, if this socket didn't have that, we're going to show you how to test it. So I'm going to put the key in accessory mode with the engine off. Then I'm going to put the right side turn signal on. You can see it's flashing. I'm going to pop the hood, I'm going to open the hood. Use the prop rod right there.

We want to test the turn signal socket for power and ground. One way to do that is: we're going to hook our test light to battery positive but because the battery's over here, and the light is over here, our test light isn't going to reach that so we're going to use a jumper wire. We just have an alligator clip on one end. We'll hook that and then we'll hook the test light down below with that. You want to make sure that other end is not touching the vehicle at all. Come over to the battery. We'll put that on the positive side, just like that. So here's our test light. This is a 12 volt test light, you can actually get these at 1AAuto.com. We're going to connect it to our jumper harness with the alligator clips right here. Now this is connected to battery positive so we're going to check to make sure that this test light works and we're just going to go on a ground, so this set up right here is for testing a ground circuit.

Then we're going to test this socket and we should have a steady light. That's blinking so that's not it. That's blinking, oh, there we go. So if I clean off some of the corrosion, I do get a steady light, so aside from the corrosion on this, this would be a working socket, but because of the corrosion, it needs to be replaced.

So we got a new socket here. Plug that in, now we can install a new light bulb. As you can see it's working properly, so we can slide it back into place. Line that up and twist it to the right.

Thanks for watching. Visit us at 1AAuto.com for quality auto parts, fast and free shipping, and the best customer service in the industry.

Tools needed for replacement:

    Diagnostic Tools

  • Test Light

  • Specialty Tools

  • Jumper Cables


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