After having the 3 amigos flashing at me intermittently, with rhyme nor reason setting them off , sometimes they'd not show for over 20 miles, then just pop up. I did a few searches but found posts mainly about earlier cars, then about the sensor needing to be drilled out as it was sure to snap if you try to remove it.
Anyway, I decided that for £20 I would fit a new sensor and be done. Here is how it went...................
Before we go any further, if you're having the same fault, with the warning lights being intermittent, then try unplugging & re-plugging the connection a couple of times to clean it first, as that is really the only part of the wiring that is open to the elements.
So if you still decide that you need to change the wheel sensor the easiest way is to remove the brake caliper and disc, then remove the hub, you can then knock out the sensor.
So, wheel off, remove the caliper from it's mounting. (13mm spanner & 15mm spanner) and take out the pads. (Now is a good time to change them if need be, but change both sides of the axle, not just one)
Now remove the caliper mounting from the main casting (14mm socket)
Next, remove the disc, now remove the bolt that holds the sensor in, you can try WD40 or similar to free it, but more than likely the plastic brkt part of it will snap off, leaving the main *barrel* part of it stuck in the casting. Now remove the 4 bolts that hold the hub to the main casting, once done, the hub will easily part from the casting and you can see the end of the sensor poking through .
I used a flat chisel against the old sensor, hitting the chisel side with the hammer, after a couple of taps it moved, then it was just a matter of using an old bolt in front of the chisel to finish tapping it out.
Once it's out, clean out the hole, then it's just a reversal to fit the new sensor.
A easy way to clean out the hole that the sensor fits in, is to put a piece of folded emery or similar into a split pin, then put it in the drill.
If it's reluctant to move, then drilling down the centre of it will weaken it, but use a smaller drill than 10mm so as not to risk drilling into the casting, also put some tape around the drill to mark the depth to go to so that there is no risk of drilling too far.
When rebuilding everything up, you may have to wind the brake piston in a little to give you a bit of clearance to get the caliper over the pads, if you do this, remember that the slot in the end of the piston must line up with the peg on the brake pad.