Headlight leveling sensor repair might have been successful

For the first time in 17 months and 33K miles of use during my tenure as a Prius owner, I just finished a non maintenance repair. I could no longer put off the repair on the HID headlight leveling sensor. The dreaded red triangle of death began appearing along with the leveling sensor icon on the MFD at least once per day about 10 days ago. It didn't seem to affect the headlight aim but I couldn't tolerate looking at that unnecessarily large warning symbol every single day. It's bad enough having that stupid cold weather icon to look at five months out of the year.


I was surprised how badly corroded two of the small springs were inside the plastic sensor case. One of the springs looked like new - go figure. It took me almost a hour to carefully scrape out all the corrosion from the cavities the springs sit in. There was practically no spring left in either cavity - it had all turned into a solid pool of tenacious rust. Luckily, the terminals at the base of each cavity were still in good condition. I tested for continuity between each cavity base and the three terminal male connector and was good to move on to reassembly mode.


I installed ball point pen springs cut in half and reassembled the sensor case after applying a lot of waterproof silicone grease to the o-ring.


It appears the repair was a success. I haven't noticed a big difference in the headlight aim, it didn't seem to be an issue before. The headlights do seem to light up the front of the road a little better. So far, no more annoying red triangle after 60 miles and five starts. I'm keeping my fingers crossed.

I'm hoping this repair will last a couple of years. We'll see.

 

Yeah, it was undoubtably road salt that caused it.

Too bad Toyota overlooked this. I'm sure that most Prius owners in areas using road salt will eventually experience the same or similar problem I did (and probably more than once).