Winter In Anchorage Engine Block

This may help
Prius to Alaska | PriusChat

 

My block heater experience is 3rd gen, but I think similar:

I've seen dealership-installed block heater prices anywhere between $250 and $400 CDN. I see currently Toyota Canada website, "building" a Prius purchase, the installed price for this accessory is $398.51 .

I got the block heater when we purchased, in Fall of 2010, and paid $400..

We use it before virtually every cold-start, typically for around 2 hours.

After about ten years and 80K kms the original block heater gave off a puff of smoke: it had shorted out, just where the wires go into the heater element. I purchased the replacement part for $90 CDN. At least for 3rd gen, the part number was PU140-00905.

I installed the replacement block heater myself. The big hurdle is access. Toyota made no provision for this, seemingly presuming it would be done at the factory, before the engine's installed.

Retroactive install was hard: there's enough room for everything, when the install is done. Just. But to install you need extra room. It's somewhat analogous to getting into a tight parking spot. The heater element is a cylinder, that fits into a pocket on the block.

There are a lot of heavy conduits in the vicinity, and it's JUST possible to cajole them out of the way, get enough room to position the heater element outside of the pocket and pushed in. Plus, you need to butter it up with a heat transfer grease (supplied).

If you DIY, I'd recommend to delay applying the heat grease. Go through the steps, get the heater element in position, ensure it can get started into the pocket, then pull it back, apply the grease with your finger tips, run the element into the pocket. Twist as you go to minimize scraping the grease off.

I ended up doing this mostly from below, reaching up with an arm on either side of the main drive shaft, more-or-less purely by feel, scraping my arms on metal edges. Great fun.

Screen grab from Toyota Canada website:



Attached is a 3rd gen block heater install pdf. I would take the routing instruction with a grain of salt. Contrary to the pdf, I ran the block heater plug-in out through the lower front grill.

You want to zip-tie it VERY securely to the grill. Also, when plugging in, use an extension that can pull straight out, and secure it to something substantial. You WILL forget to unplug, at least once, likely more, and so plan accordingly. You don't want to be dragging the block heater plug along the road, or trailing the extension cord.

 

I'd probably tie it to the radiator brace, the grill plastic can snap pretty easily in cold weather.

Also helps to wire in a small nightlight in the grill area- that way you can tell the block heater has power by looking out your window instead of suiting up.

The block heater isn't necessary for storage, not by a long shot. Just helps a lot for comfort and getting something close to good MPG.

Cold weather is not bad on the hybrid battery, but lack of use is relatively hard on it. If there is any way to keep the car in active use, or at least driven around the block monthly, this would be of great benefit. Lots of stories of Priuseses of about that age put away for a few months and never coming back.

Good luck!

 

These illuminated pass-through gizmos are good:

 

All good points, but I am going to resurrect this thread to add this from the Battery University website:

Batteries can be discharged over a large temperature range, but the charge temperature is limited. For best results, charge between 10°C and 30°C (50°F and 86°F). Lower the charge current when cold.
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We can't lower the charge current on a Prius. It does get to high rates with regenerative braking. I think it does make sense to have the car parked in [Ready] until the cabin temperature gets above 50 degrees F. For her daily commute, my wife always goes outside to warm the car up and comes back inside.

This habit certainly does not help fuel efficiency. But she is comfortable and I take comfort in that the traction battery is also happy when she heads down the other side of the mountain.

Since YMMV, watching the BATT temperatures in the Dr. Prius App would be helpful feedback until one gets a sense of when the HV battery is warm enough to proceed in your terrain.