Here are step by step directions on the install. Pics below.
Step 1: Search Ebay and order: 89121-50020
Step 2: Unpack your new sensor and wrap electrical tape around the tabs so you'll be able to get the sensor out of the dash in the future (Thanks for the idea MC1986). I found that cutting a 3-4 inch long piece in half LENGTHWISE was strong enough to hold the tabs. I originally did not cut in half and it was too thick to fit back into the dash.
Step 3: Select credit or other card for sensor removal (I prefer the Costco card myself).
- Note - I tried my smallest trim panel removal tool first but there is just no good angle.
Step 4: Work the card under the existing sensor head on the WINDSHIELD side and pull upward.
Step 5: With the sensor removed from the dash but STILL CONNECTED, put a hanger, pipe cleaner, or other item through the wires so it doesn't fall back in the hole.
Step 6: Remove factory sensor. Plug in aftermarket sensor.
Step 7: Test sensor by turning the ignition on, turn on your headlights, turn off the lights in the garage, the instrument panel should be lit dimly. Put a flashlight over the sensor - the instrument panel should get lighter.
Step 8: Remove hanger/pipe cleaner from the wires and insert sensor back into dash
Note - you have Entune go to post 56 on this thread (page 4) from Electoboy for steps to get the radio/nav to dim