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Due to my environment/usage, I require as large of a 12v AGM battery that I can install in the NX450+.
The stock battery fitment does not show on many websites so here is the info.
To access the 12v battery there is an easy to remove door where typically a spare tire would be.
The label states "P5" and 345 cold cranking amps. It is a Group 96R battery.
The shop had a tool that they put into the OBD port which preserved the settings.
Some unexpected behavior happens when you disconnect the 12v battery such has headlight flashing and the hatch won't close automatically the first time.
The owner's manual has a large section on the 12v battery if you are interested.
Due to my environment/usage, I require as large of a 12v AGM battery that I can install in the NX450+.
The stock battery fitment does not show on many websites so here is the info.
To access the 12v battery there is an easy to remove door where typically a spare tire would be.
The label states "P5" and 345 cold cranking amps. It is a Group 96R battery.
The shop had a tool that they put into the OBD port which preserved the settings.
Some unexpected behavior happens when you disconnect the 12v battery such has headlight flashing and the hatch won't close automatically the first time.
The owner's manual has a large section on the 12v battery if you are interested.
Just out of curiosity, where are the jump/charge connections for the 12v? I've had cars with 12vs in the back, but they had connection points under the hood so you could jump the car normally if needed. I've skimmed the manual, but missed seeing this....and also missed finding the batter itself although I stopped after trying to gently pull off the plastic covers after lifting the cargo cover thing. Nothing pulled up easily (other than a side cover plate) so I stopped intending to read more about it.
Similar to other hybrids, there is a front jump start location on the driver side where you have a positive (red) terminal and you attach the other to the frame in the centre of engine. Page 690 of manual
Similar to other hybrids, there is a front jump start location on the driver side where you have a positive (red) terminal and you attach the other to the frame in the centre of engine.
Page 690 of manual
Thank you! Looks like I won't be installing my battery tender's easy connector in this car..... But the NX should see enough regular driving not to need it.
EDIT - Saw another thread with a photo of the battery (still haven't gotten back there myself) and the tender detachable connection will fit nicely attached there, so I'll be hanging it out the back of the hatch whenever I need to connect it to the tender.
My 2018 ES350 had a bad battery. Dealer replaced it with another “Lexus” battery but because we don’t drive much these days… replaced it two weeks ago with an AGMInterstate Battery.
I did connect up the battery tender during the swap and didn’t lose any settings.
I’m not sure about our NX but 2018 has that radio ID and I was told to make sure to save that code.
I am hoping that because the 12 v battery is charged by the hybrid battery it won’t be an issue with the NX.
Last edited by RKF350; 03-04-22 at 10:39 AM.
Reason: Spelling
My 2018 ES350 had a bad battery. Dealer replaced it with another “Lexus” battery but because we don’t drive much these days… replaced it two weeks ago with an AGMInterstate Battery.
I did connect up the battery tender during the swap and didn’t lose any settings.
I’m not sure about our NX but 2018 has that radio ID and I was told to make sure to save that code.
I am hoping that because the 12 v battery is charged by the hybrid battery it won’t be an issue with the NX.
I was under the impression the 12V is not charged by the hybrid battery, but that's based on older hybrids. There's a lot of focus in the manual about ensuring the 12V is charged otherwise....
Due to my environment/usage, I require as large of a 12v AGM battery that I can install in the NX450+.
The stock battery fitment does not show on many websites so here is the info.
To access the 12v battery there is an easy to remove door where typically a spare tire would be.
The label states "P5" and 345 cold cranking amps. It is a Group 96R battery.
The shop had a tool that they put into the OBD port which preserved the settings.
Some unexpected behavior happens when you disconnect the 12v battery such has headlight flashing and the hatch won't close automatically the first time.
The owner's manual has a large section on the 12v battery if you are interested.
Just curious, why do you need to make this change?
Why not connect directly to the battery in the trunk?
Originally Posted by ct6978
Thank you! Looks like I won't be installing my battery tender's easy connector in this car..... But the NX should see enough regular driving not to need it.
EDIT - Saw another thread with a photo of the battery (still haven't gotten back there myself) and the tender detachable connection will fit nicely attached there, so I'll be hanging it out the back of the hatch whenever I need to connect it to the tender.
Why not connect directly to the battery in the trunk?
It appears as though the 350 probably has a larger 12v battery than the 450 plug in, judging from cold cranking amps in each. I would have guessed the same 12v battery throughout the NX models.
Also Odyssey not available everywhere. These images are from US Autozone.
Revitalizing this old thread because its on topic. I'm searching to replace my stock Lexus/OEM 12 V battery with a larger reserve capacity one - to not have to worry about a dead 12 V. Although I have a RX450H+ it has the same problem (probably with higher risk of dead battery due to higher parasitic load), since it apparently has the same 12 V battery and its management system as the NX450H+. There are at least 2 threads in the 5th Gen RX forums with a lot of data collected by many folks including myself, related to the 12 V battery needing jump starting and high risk of dying - despite using them in mild California winters, having reasonable use (~100 miles of regular driving per week) and some (at least 2 folks) even proactively using battery maintainers to prevent dead 12 V battery and still ending up dead. So its really an unavoidable design flaw at this point, the root cause of which we believe has to be really fixed by Lexus - but we are just trying to figure the best we can so that we don't have to worry about it, in case replacing with a "better" battery paid out of our pocket would help.
Now questions for those that have replaced the stock/OEM and found the problem completely disappear on the NX450H+:
1) The AGM battery cited in this thread is specified with a charging voltage of 14.4 - 14.8 V. While in the RX450H+ at least, we have measured charging voltages at 14.2 V approximately, with real-time measurements through the ODBII port and also from visual observations with a monitor at the 12 V lighter port. For those who have done this replacement with AGM in other Toyotas and explaining on Youtube, they seem to have used a diode attachment in the place of a fuse to trick their alternator (ICE trucks) into outputting a larger charging voltage necessary for AGM batteries. Is that higher charging voltage not necessary for the NX450H+ ? Or was it taken care of in some other way ? And did the dead battery problem go away completely after the Odyssey battery replacement ?
2) If not an AGM - is there any other flooded lead-acid battery anyone has replaced the stock/OEM battery with - to mitigate (lower the risk of occurrence) of a dead 12 V ? Please advise what battery you chose in that case ?
Thanks much in advance!
Adding Odyssey battery specs screenshot:
Last edited by wrinkle; 04-28-24 at 08:31 PM.
Reason: adding battery specs screenshot
Update. Since I posted this initially, the 12v battery depleted (died) due to weather (Feb 2023, Jan 2024). This was due to the weather being -20C for about 4 consecutive days. The 12v withstood any ACC related drainage that was not due to weather. I used a lithium ion battery pack (NOCO) to boost the car from the connection under the hood. Have not used, nor plan on using a trickle charger/maintainer.
Update. Since I posted this initially, the 12v battery depleted (died) due to weather (Feb 2023, Jan 2024). This was due to the weather being -20C for about 4 consecutive days. The 12v withstood any ACC related drainage that was not due to weather. I used a lithium ion battery pack (NOCO) to boost the car from the connection under the hood. Have not used, nor plan on using a trickle charger/maintainer.
Thanks for the update - in the update above, by “12 V” you are entirely referring to the Odyssey ODP-AGM96R, correct, just to be clear ?
03-04-22, 05:51 AM
NX450+ upgraded aftermarket 12v battery
Why not connect directly to the battery in the trunk?
