Hello all, So I went to get an oil change today as well as a state inspection and the mechanic mentioned that I'm missing the Master Cylinder Cap (which seems to be the cap on the brake fluid reservoir). I took a look and it is definitely missing somehow... Obviously, it's terrible to be driving around without this cap and I'm not sure how it went missing and the mechanic seemed to have no idea where I could get another one. I've tried all the local places and online but can't seem to find just a replacement cap. I've covered it up in the mean time but am really struggling to find a replacement. Any suggestions?
Find a junk yard with Prius... Preferably a yard that allows you to pull your own parts. It's good to know where these places are for future odds and ends that break or go missing.
The master cylinder cap is pretty much universal for Toyota for 20+ years. The part # is 47230-12040.
A little history, where do you get your oil changed and when was the last one, obviously the technician left it off, as brake fluid is suspectable to air, and absorbes air, time to flush all the fluid and start over, the dealer that changes your oil should work with you, if not do it anyway, then find a more trustworthy dealer.
By susceptible to the air you mean it absorbs moisture and you don't want water in your brake lines? Or do you mean break fluid can deteriorate due to oxidization?
Put something on in the interim, say plastic and a rubber band? Maybe punch a single pin hole in the plastic so it's not completely air-tight.
That one is used on many models, but not on any Prius cars. The parts catalog for a 2010 Prius, in Figure 47-02, Brake Master Cylinder, gives two part numbers: 47230-11010 (plain cap) or 47230-20140 (with valve), depending on production date.
I would be more worried about dirt getting into the master cylinder than anything else. Moisture can be purged thru a good fluid flush. Dirt is another thing. It can get stuck at the seals and damage them.
