Hello. My '05 Prius has served me well for nearly 100,000 miles, but lately has started to have a couple odd problems, starting with the coolant. Had the coolant changed a few months ago; the garage recommended it due to the extreme heat here. They told me all coolants are the same; they use a colorless coolant and add the correct color to it. Seemed odd at the time, but I let them do it. Now, about 3 months later, they're telling me there was electrolysis due to a weak battery (the little battery). I knew the battery was due for replacement and replaced it. But the notion that that would affect the coolant makes no sense to me, so I did not allow them to change the coolant again. Got some litmus paper and tested the pH, and sure enough, the pH was only 7 (I think it should be 8 or higher). So clearly the coolant need to be changed. But the question is, why? Is it because of the failing battery? Or is it because the garage botched the first change or used crummy coolant? What do you think?
Did they put Kool-Aid in your cooling system instead of Toyota SLLC? Find another mechanic pronto or better yet, DIY.
Agree, that assertion that all coolants are the same is a bunch of BS. They should be using Toyota SLLC. There are some coolants that aren't long life. There's also the infamous DEX-COOL Antifreeze | ACDelco on some GM cars. If it didn't matter, Toyota/Tesla wouldn't have put on a warning about not mixing coolants that I mentioned at My Nissan Leaf Forum • View topic - Official Toyota RAV4 EV Thread on the Rav4 EV.
I think that the colorless coolant is aka water or H2O, and then dye was added. I agree with your assessment that the coolant needs to be changed again and hopefully you'll find a more reputable place to do that service.
Just to add (and hopefully clear this up), there is zero chance that "electrolysis occurred due to a weak battery". That statement is laughable and a total fallacy. Did this truly happen? Or... is this a made up story???
