You don’t mention your model:trim bit I assume it’s a Luxury trim with electric rear seats. Surely there’s a manual release to enable lowering of the seats without power!

 

Not that I've been able to find.

 

Correct, I have the what's called the "Executive Package" in Canada with electric fold rear seats. I've searched far and wide and can't find any evidence of a lever or a feature like that documented anywhere.

 

The only thing I found in the Lexus tutorial video is a manual release handle on the top and back side of the center console. If the luxury model indeed has this, it may provide an entry point, albeit small.

 

This is what I did - by laying sideways in that center section folded down I was able to reach the manual release cover on the rear hatch. FAR easier to put power on the jumpstart positions and open it that way...

BTW my battery was dead because I spent 2 hours installing my rear dashcam - the headlights were on the whole time I think. It's weird how Lexus doesn't have any software to protect the 12V battery...

 

Thank you for updating us on how your battery died, Meeker.

Mental note to self: Hook up Battery Tender or trickle charger to 12v battery any time maintenance is being done for a lengthy period of time.

There ought to be a way to turn off the headlights when the cargo door is open for extended periods. Why does Lexus even think we need headlights when the cargo door is open?

 

Meeker’s predicament got me to thinking…

I might try buying a long, extension ring connector cable to hook onto the 12 volt battery and run it along the edge of the cargo floor to behind the passenger seat near the door. It will easily be reached by either a booster block, battery tender, or a full blown battery charger. This would eliminate hooking anything up under the hood or having to worry about the cargo door not operating and having to crawl into the cargo area to fiddle with the emergency door release. Something like this:




Thoughts?

 

Due to the storm, my 3-year old RX350h sat in an unheated garage for 5 days, with its original battery. Yesterday it started instantly and went on a small uneventful shopping trip.

Had no trouble starting and stopping on unplowed roads, with the Goodyear tires. Texas appears to have zero equipment to cope with snow and ice.

 

Well, it depends on where in Texas you’re located. Some parts rarely see any significant ice. Snow is not a big deal and is relatively easy to drive on. Back in the 60s, in the Panhandle, we actually did Drivers Ed in the snow.

There is a lot of snow removal equipment, as well as trucks that spread sand and spray anti ice solutions, but only the highways and major streets are going to get treatments. Priorities, ya know?

We just plan ahead and stay home on the rare occasions we get ice or snow here in SE Texas. If you’re prepared, there’s no need to get out in it.

 

Hey Kensterfly, great idea but for trickle charging only, not boosting. At least that's what someone mentioned on here before.

 

The initial inrush of current from a jump pack into a dead battery is too much for a charging pigtail like that. The fuse will pop to protect the wires.

 

I had been going down this exact idea 1+ years ago, on this thread, if you look back - my bet was that getting a thick enough cable with the ability to carry 20+ Amps for a very short time would be enough - however the fuse might blow depending on the battery's state - such that if the stock battery were at 3 or 2 V depending on its state of degradation, the solution wouldn't work. However, finding and having the Emergency Start completely eliminated any such hack's need - as it works for all such scenarios as the method that always works.

I do have a trickle/charger connected in the same manner now with the wire running to the rear window from the battery, but only for trickle-charging/maintaining at home, if/when I'm on travel. Rest of the times, including leaving the car at airport or away from home/garage, the Emergency Start is the perfect solution that works in ALL situations for me. That solution works even if stranded in a remote national park or some such places or stuck in a place where the car can't be easily put on a flatbed - where even getting Roadside Assistant or AAA might be close to impossible and at the very least cost a small fortune or hours/days. And even in a situation if the stock battery is permanently dead, the ES can still serve to drive the car to the dealer/store for battery replacement.

 

Has anyone actually tried to document the amperage required from the 12V battery for starting the RX?

IIRC it is the hybrid battery that actually turns the ICE starter.

AI sez:
There is mention that having the headlights on increases the required power, since that amperage is drawn from the 12V battery as well.
I SEARCHED 'Toyota' hybrids since those are more common.

 

Would a non fused cable or higher amp fuse (50A) work?

The 10 gauge cable itself should be fine, shouldn’t it?

 

I haven't checked the starting current as I would need a helper, but its probably similar to the Prius Prime in the video below, which pulls about 35 amps at system starting. Of course, that would be on top of any other loads.

I recorded the following
ACC mode = 25-30 amps
Following include ACC amps
Headlights on = 40-45 amps
Heated steering wheel or seat = 34 amps
HVAC = 36 amps

Immediately after starting, I observed a 12v charging current of 56 amps, which tapered down quickly. The video below sees 46 amps charging current, tapering quickly.

There is not a "starter" per se, but a motor-generator that is part of the the hybrid system. One of its functions is to start the engine.

A dead battery can initially pull well over 100 amps, more the "deader" it is. Even a freshly charged battery will initially pull over 50 amps.
Vehicle start around 15:30: