The last couple of weeks I had some cases where my 2010 450h wouldn't start on the first try. Yesterday, when I tried to start it, it wouldn't do it. After a number of tries there was no more power and everything went dark. I then realized that the 12v battery was probably the cause. I'm pretty sure that it's the original Panasonic battery so 13+ years is very good.

The problem with no power was that I couldn't open the rear hatch. Apparently, there is a release (didn't know that at the time). I was able to work from inside to get at the battery. I wasn't able to remove the rear bolt holding the battery down but I was able to twist the retaining bar enough that I was able to get the old one out and the new one in.

I've read some stuff on the internet claiming a very reasonable Lexus price for a replacement battery. I called the local dealer and it would have come to about $600 (CAD) with tax. It wasn't easy to find a proper replacement but NAPA had one that was almost identical in size (and guaranteed to fit the 450h!). It doesn't require a vent. Their price was about $230 (CAD).

Put the new one in this morning and everything is working fine. Need to reset the radio and probably bluetooth but overall, a very successful end.

 

Whats the make and model of the replacement battery?

 

That sounds suspect. What type of battery is it?

 

See this sticky thread that is the first one on the page for this vehicle!
https://www.clublexus.com/forums/hyb...rx450h-19.html

It must be only available in Canada and it has to be an AGM battery as they do not need vents. I checked US NAPA and Batteries Plus and neither had a battery for a 2010 Lexus RX450h.
Auto Zone did not have a battery.

A check of a couple of US Lexus OEM parts places appeared to indicate that the battery was no longer available.

 

Just FYI, there is a 12V boost/charge point under the hood too, no need to crawl into the back.

 

Where is that located?

 

 

Two follow up questions. 1) Can't you simply manually open the trunk lid even if the battery is dead?[ The video suggests you cannot, and 2) I have a battery jump starter I bought just in case. Can I jump start from that front engine fuse box connector or does it have to be connected directly to the battery in the rear?



er QUOTE=zmel;11652013] [/QUOTE]

 

First statement is partially correct. In order to pop the hatch you need 12v or slightly lower as the hatch release is battery operated. You can crawl over the back seat and do the trick to pop the rear hatch or try to roll back the carpet etc.

Second requires the understanding that the 450H does not have high current demand from the 12v battery [installed or jumped]. There are terminal posts in the engine compartment which are small in size [standard size jump cables are too fat to get in there]. If you turn off the headlamps [take it out of auto] you can energize the electronics with a much smaller 12v source.

Salim

 

OK but I think your only referring to charging the electronics right? I'm talking about starting the engine. Or are we talking the same thing?

 

12v battery in 450H does not spin the starter. 12v starter is in the non-hybrid engine. The hybrid ICE is started by the high voltage battery which spins the wheels also spins the engine. CCA ratings on the battery are not put to use in hybrid RX.

Salim

 

This is the battery that I used:

NAPA 12V Battery

 

In your first post you mentioned that your new battery "doesn't require a vent". The photo of the "maintenance free" battery you posted is a type of "sealed battery" ... but it is still a liquid filled, lead acid battery. Your photo shows two vents - one on each side of the top cap.

Sealed lead acid batteries are not truly sealed. If the battery were to overheat, say due to excessive charging, gases could build up and cause the unit to explode. As such they have pressure valves which allow gases to vent at a certain point.

You will want to make sure that the two vents on your battery have been vented out of the passenger compartment, similar to what your OEM battery was. If the two vents are in communication with each other, you can plug one vent and vent from the other. If they are not in communication, each vent should be separately vented.