How reverse works with the electirc motor?

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Apr 17, 2021 | 10:38 AM

mclain89

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From: MA

How reverse works with the electirc motor?

How do the electric motor and reverse gear work on the 2018 RX 450H? What happens if say, the engine is off and I shift into Reverse; then I push car backward? Is the reverse gear actually engaged at all in this case? Is there any harm to any part of the drive train happening when doing this?

Apr 18, 2021 | 03:24 AM

JSracer

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From: MN

why push it ?? why not toss it in N then push it ??

Apr 18, 2021 | 04:24 AM

mclain89

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From: MA

I ask the question because recently ran into this situation. Had parked nose in into a parking garage. The battery had died a couple of months later. Then I could not jumpstart it because some pipe would not let me open up the hood. Had to call roadside assistance; they came in and BEFORE they lifted the rear wheels and tow the car a few feet back, they SHIFTED the gear into reverse first for some reason. I was worried that this might have caused some harm somewhere.

However, reading how CTV works, it seems shifting into reverse before towing the car backwards for a few feet should have been fine? Is that correct?

https://autoportal.com/articles/cvt-...ium=ForumLinks

Apr 18, 2021 | 01:26 PM

ukrkoz

Racer

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From: wa

Reverse is electric ONLY.
There is no reverse gear. Motor in the rear simply changes direction.
Gear shifter is a joystick, telling ECU, which gear selection you prefer at the moment.Even the "gear selection" is misnomer, as there are no gears to shift through.
Your battery, 12V one, should be in the trunk. Driver side. Though, it is not recommended to jump start off 12V directly, but from jumping points under the hood yet, you can jump direct.
As far as you had "gear shifter" in Neutral, you are fine.
If you have well charged HV battery - yes, you have TWO batteries - you can back out in EV only but not for long, ICE starts pretty much right away.

Apr 19, 2021 | 06:12 PM

mclain89

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From: MA

Thank you. Actually, the gear was in Reverse and that's what got me worried a bit.

Apr 19, 2021 | 07:45 PM

ukrkoz

Racer

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From: wa

Thing about towing hybrids is that when wheels spin, they rotate MG and produce or can produce electric current, acting as generator. Towing with spinning wheels is prohibited not to fry electronics and traction battery. In Neutral, there is no charging produced.

Apr 27, 2021 | 08:41 AM

Verndog08

Driver

Joined: Dec 2020

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From: Wa

This brings up an interesting question. I'm now wondering if the electric rear only motor for reverse has enough power on it's own to backup a 3500# trailer up a steep incline? The towing I've done has been on level ground but now curious on it's limitations under different conditions?