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How to Replace ABS Sensor 02-05 Mercury Mountaineer

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  1. step : Removing the Wheel (0:42)
    • Pry off the center cap with a flat blade screwdriver
    • Loosen the lug nuts with the vehicle on the ground
    • Raise the vehicle with a floor jack
    • Secure the vehicle on jack stands
    • Remove the lug nuts
    • Pull off the wheel
  2. step : Inspecting the Brakes (1:12)
    • Turn the rotor by hand or turn the steering wheel to turn the rotor
    • Check for gouges on both sides of the rotor
    • Check the thickness of the brake pads
    • Check the brake pad wear indicator
  3. step : Removing the Brake Pads (1:47)
    • Unclip the ABS wiring from the wheel knuckle with a flat blade screwdriver
    • Remove the two 14mm bolts from the brake caliper
    • Pry the brake pads into the caliper with a flat blade screwdriver to push in the pistons
    • Pull the caliper aside
    • Secure the brake caliper with wire ties
    • Pry the brake pads off with a flat blade screwdriver
  4. step : Removing the Brake Rotor (3:29)
    • Remove the two 18mm bolts from the brake caliper bracket
    • Pull off the brake caliper bracket
    • Pull the rotor off
  5. step : Removing the ABS Sensor Wiring Harness (3:52)
    • Disconnect the ABS sensor wiring harness behind the radiator reservoir
    • Remove the 5mm Allen bolt that holds the ABS sensor wiring harness to the hub
    • Disconnect the ABS sensor wiring harness at the hub
    • Unclip the ABS wiring from the frame
    • Pull out the ABS sensor wiring harness
  6. step : Installing the ABS Sensor Wiring Harness (4:50)
    • Connect the ABS sensor wiring harness at the hub
    • Tighten the 5mm Allen bolt that holds the ABS sensor wiring harness to the hub
    • Feed the wiring harness into place
    • Clip the harness to the frame
  7. step : Installing the Brake Rotor (5:56)
    • Slide the rotor on
    • Thread on one lug nut to hold the rotor in place
    • Put the caliper bracket back into place
    • Start the two 18mm bolts by hand
    • Tighten the 18mm bolts to 85 foot-pounds of torque
  8. step : Installing the Brake Pads (6:41)
    • Apply grease to the brake pad tabs
    • Install the new brake pads into the bracket
    • Remove the wire tie from the caliper
    • Put the caliper on
    • Thread the two 14mm bolts by hand
    • Tighten the 14mm bolts to 25 foot-pounds
  9. step : Reattaching the Wheel (7:49)
    • Clip the ABS sensor wiring into place
    • Wipe down the rotor
    • Remove the placeholder lug nut
    • Slide the wheel into place
    • Start the lug nuts by hand
    • Tighten the lug nuts preliminarily
    • Lower the vehicle to the ground
    • Tighten the lug nuts to 100 foot-pounds in a crossing or star pattern
    • Reattach the center cap
    • Connect the ABS sensor wiring harness behind the radiator reservoir
  10. step : Testing the Brakes (9:05)
    • Pump your brakes repeatedly until they feel firm
    • Test your brakes at 5 miles per hour and then 10 miles per hour
    • Road test the vehicle

Brought to you by 1AAuto.com, your source for quality replacement parts and the best service on the Internet.

Hi, I'm Mike from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.

In this video, we're going to show you how to replace the ABS harness on this 2003 Mercury Mountaineer and we show you on the passenger side, but the driver side is the same procedure. The items you'll need for this is a new ABS harness from 1AAuto.com; a 14mm, 18mm, and 19mm socket and ratchet with a piece of pipe for extra leverage; a 5mm Allen bit or wrench; flat blade screwdriver; jack and jack stands; and a torque wrench.

Pry off the hubcap by using a flat blade screwdriver in the small slot on the side. Once you get it started, you can just pull out around the edges. We'll just fast forward as Mike removes those 19mm lug nuts. If you don't have air-powered tools, you want to loosen them while the vehicle is on the ground, raise the vehicle and remove them the rest of the way. Now you can pull the wheel free.

You want to just inspect your brakes. Just take your fingernail and go up and down. You're feeling for any grooves. Small grooves are okay, but anything that really gets your fingernail stuck in there or anything is a little too much. You want to either replace your rotors or turn them down. Do the same thing on the back side. You can see the inner pad here. That's got some pretty good life left on it. Then the outer pad, if you look right here, you see between the metal here and the rotor. There's good life on that. The brakes are actually in really good shape on this.

Now just open up this clip with a flat blade screwdriver. You just have to pry the tab and pull it open. Just pry the harness out of this clip and pull it out of these three. Then you want to remove these two 14mm bolts. We'll just fast forward as Mike does that. Now, using a flat blade screwdriver, just pry right here and that will push the piston in on the caliper and make it easier to pull the caliper off. Do it again down here and pull the caliper free. You want to set it up and out of the way so we're just going to put it up here. Just to make sure it doesn't fall down, use a wire tie to just secure it up there. Now pry out your brake pads. The best way to tell the life left in your pads is this little slot right here is a wear mark, so you can see it pretty much goes away once you have about an eighth of an inch of pads left. Like I said before, these pads have quite a bit of life left on them.

Now remove these two 18mm bolts. You can see he's using a piece of pipe for some extra leverage. When you pull out the last bolt the caliper bracket pulls free. Pull your rotor off.

Now up here, you want to just reach down here behind your radiator reservoir and just push on the tab on this harness and pull the harness free. Now, just remove this 5mm Allen bolt and you can use another wrench for some extra leverage, if you're using an Allen wrench. Once you break it free, just remove it, and then the harness will just pull out. Then just open up this clip up here with a flat blade screwdriver and then pull the harness down.

Take your new harness and push it into place, then replace that 5mm Allen bolt. Just tighten that up. We're just going to use our old clips. We're just going to pry off the new clips and you could always just pry out your old clips and push these ones into place, but ours are in good condition, so we're just going to use them. Feed the harness back up and get it up over the control arm and then just clip it back into that clip. Push it back up into place.

Take your rotor and push it into place and then replace a lug nut just to hold it there while you reassemble the caliper bracket and caliper. Now take your caliper bracket, line it up and then just replace those two 18mm bolts and tighten them up. Then torque both of those to 85 foot-pounds.

Push the brake pads back into place and it helps if you have some brake grease on the tabs to help it slide in to those brake pad slides. Now, remove your wire tie and pull your caliper back down. Then take your caliper and push it back into place over your brake pads. You want to make sure that those slides push down underneath and line up. Once they're lined up, replace those two 14mm bolts and tighten them up. Then torque both of those to 25 foot-pounds.

Then just push this back into those three clips and then back into this bracket and then close that final clip. Wipe down any dirt you may have gotten on your rotor while replacing the caliper and then remove that lug nut.

Replace your wheel, then replace all the lug nuts and tighten them preliminarily. Then you'd want to lower the vehicle and tighten them the rest of the way, then torque each of these in a crossing pattern to 100 foot-pounds. Now replace your hubcap. Just line it up and hit it back into place. Then just grab your harness up here and push it back into the connector until it clicks.

Whenever you've done any work on your brakes you want to just pump the brake pedal until it firms up. Then you want to do a stopping test from five miles per hour, then 10 miles per hour.

We hope this video helps you out. Brought to you by www.1AAuto.com, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.

Tools needed for replacement:

    General Tools

  • Hammer
  • Jack Stands
  • Floor Jack

  • Hex Wrenches

  • 5mm Hex Wrench

  • Materials, Fluids, and Supplies

  • Cloth Rags
  • Wire Ties
  • White Grease

  • Ratchets & Related

  • Ratchet
  • A Piece of Pipe (for leverage)
  • Torque Wrench

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - Metric

  • 14mm Socket
  • 18mm Socket
  • 19mm Socket

2002 - 2005  Ford  Explorer
2002 - 2005  Mercury  Mountaineer
2003 - 2005  Lincoln  Aviator

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