I'll break this into two questions. First, can I take a self-dimming homelink mirror from a 2009 and which has a compass built in and put it into a 2010 with its self-dimming homelink (but no compass) with plug-and-pay ease -- that is, without modifying wire hook-ups etc. In other words, is the same model of mirror used in 2009 and 2010, or are they at least compatible enough to be inter-changeable? I do intend to ask the dealer's parts-and-service dept to check the stock numbers. If they're the same, I'm ok. But if they have the 2010 mirror under another part number, it may or may not fit. Hence this question. Second, take the first question, and then suppose the 2010 has the basic mirror which is not self-dimming (and no homelink) -- would the 2009 mirror fit into it with plug-and-play ease? In part, that also means -- is the correct wiring harness for it hiding behind the trim though it can't be seen? Thanksfor any help you can give!
AFAIK, the 2009 Prius' auto-dimming mirror does not have a compass. It's the same design as the 2010 (i.e. auto-dimming w/ Homelink) but of course the 2010 will have the newer mirror design. (at least compared to my 2005. I do not know if it was updated for 2006). You can install an auto-dimming mirror to almost any car. You just need the right mounting brackets and a source of power.
Thanks for the info. I can tell that I didn't explain my starting point well. I neglected to say that I had replaced my auto-dimming w/ Homelink with a mirror from a Toyota Avalon which was auto-dimming w/ Homelink plus compass. Now that I'm considering upgrading to a 2010, I'm trying to figure out whether I can move the Avalon mirror to the 2010, and take the 2010's mirror and put it in the 2009. I should say that I really enjoyed trying to get an aftermarket compass to work inside the Prius. I bought several different models from auto stores and the internet. Tried them all on everyplace on the front & top of the dash, plus two I tried to suspend on the ceiling. I could get them perfectly set up sitting in the driveway ... and all was well until I drove a bit -- then the compass readings had a mind of their own. I concluded that it was probably some combination of (1) being too close to the electrical fields of the dash, (2) not being able to calibrate in whatever way the mirror's compass does, and (3) it was possible the mirror's compass had better shielding. Who knows ... but it did work!
okie dokie then lol. There is a method to calibrate the compass. I don't remember it (and I can't refer to the manual cause our Camry is now gone). Do you still have access to the Avalon's owner's manual?
Alas, I never had the Avalon. Instead, as to the Avalon mirror with compass, as Wierd Al sang it: ... "I bought it on eBay ...."
Instructions here Turn ignition on. Zone variation needs to be changed to use in different areas of the country. For a different Zone selection, push in the Comp switch for 3 seconds until the Zone selection comes up. Release, then toggle until correct zone is found and release switch. To re-calibrate, hold the Comp switch for 6 seconds until a "C" is displayed. Drive your vehicle in at least 3 circles, allowing 45 seconds to complete one circle. So either the zone is wrong or it has to be re-calibrated.
I don't know about Toyota's GPS, but the Garmin GPS definitely has a compass built in. You may want to consider a GPS as your compass.
