Inverter Coolant Overdue

Just my own opinion. The inverter coolant doesn't seem to be subject to the same conditions as the engine coolant. This makes it less susceptible to the chemical changes that require a coolant change. My engine coolant changed to a bit orange-ish as compared to the inverter coolant still looking just like the factory new coolant. I really don't think the extra 13K is going to cause any real problems.

Any good mechanic would be able to replace both coolants, but there are a lot of them (who aren't good mechanics) who seem to think that working on a Prius is beneath them. The important thing (again in my opinion) is that they use the factory coolant (available at the dealer's parts department) and don't try to mix it with some aftermarket crap.

It's really not that hard to do by yourself, but it can be a bit messy. Here's a video on it.

I don't know much about Chicago, but the guy's shop is in Homer Glen. (TCCN Automotive - Address in the About section of his YouTube channel). Probably a ways away, but hopefully not too far. I don't know about his rates though.

 

What’s the miles on it now?

FYI: Toyota USA says 15 years or 150k miles for inverter coolant change.

if you’re missing the Warranty and Maintenance Booklet, a pdf can be downloaded from Toyota Tech Info website (just Google that).

I’ll post a spreadsheet/pdf table-format translation of the booklet’s schedule in a sec, much easier to read.

 

Good Catch!! You'll be OK. If your curious about how bad the issue is, you can do a litmus test of the old coolant. Most people think that they don't need to change it, if they don't live in an area that gets "hard freezes". The reason your suppose to change it is because over time the coolant becomes acidic. I've seen many old iron block engine coolant turn brown from neglect (engine rusting from the inside out; also breaking down internal seals and gaskets). Modern aluminum block engine coolant doesn't change color; but the internal seals, gaskets, electronic components are slowly being eaten away when the coolant goes acidic.

Hope this helps....

 

[QUOTE="Aubstacle, post: 3485186, member:Also, my mechanic insists that people shouldn’t be changing their inverter coolant on their own because the hybrid system is involved and special grounding cables are necessary. Is that true? Seems to be s out of people doing it themselves.[/QUOTE]

Find another mechanic!! This clown doesn't know what he's talking about!!!

Have you replaced the ATF?

 

Run - don't walk. Get away from that guy as fast as you can. There are special cables for the hybrid system. They're bright orange. You won't need to touch any of them to do an inverter coolant change.

 

At first read yes, and this confuses the hell out of nearly everyone. At the 100k mile service they say:



But note the diminutive "3" at the end. If you go two pages forward, you find this:



Also, if you look on the side of the inverter coolant, you may see this:



This is on the reservoir of my 2010, Canadian spec. FWIW, Toyota Canada says to ignore it and change both at 10 years or (roughly) 100k miles.

And as mentioned earlier, I've attached Excel and PDF format summary of the American schedule, in easier to read table format (both the as printed schedule, and another where I've extrapolated out to 240k miles..

 

This video is pretty good explanation of the inverter coolant change:

This video is for the engine coolant change:

The second one is "mostly" spot-on, but the Repair Manual instruction varies from it, towards the end, instead recommending to refill to the "B" line on reservoir, replace the cap on the reservoir, and run the car till fans come on. I'd say and/or till 30 minutes have past.

Both of the above videos are linked here as well, plus a lot of others:

Nutz About Bolts Prius Maintenance Videos | PriusChat

And I've attached a Repair Manual excerpt, for both engine and inverter coolant change

 

The other fluids worth replacing, but NOT mentioned by Toyota USA, are brake fluid and transaxle fluid. See my signature for info on those. If you're viewing on a phone turn it landscape to see signatures.

I've done all of the above; they're all readily doable, without special equipment. If you can manage an oil change you can do these.