Just curious, what are you trying achieve by replacing your battery with an AGM?

 

When the battery died in our RX I found the key difficult to unlock the door. I gently used a pair of pliers and a soft rag to twist the key. Lube is a great idea! Dang I shoulda thought of that!
I replaced the battery with an Interstate AGM from Costco for about $160 as I recall.

 

I just restored my battery using a Pulsetech xc400 and a BatteryMinder 2012. Originally it was 67% at the dealer’s lot. No pic

 

Shell shocked from what Lexus wants to replace the battery (I could almost buy 3 top quality batteries myself for the same cost). A) Is pulling the battery without temporary power source a minor annoyance of resetting a few things like the time or a major nightmare (say for example remote key FOBs no longer registered, critical settings lost, who knows/whatever) and B) If I don't register the new battery in the car's computer (because of replacing it myself and not having the instrument that does it) will I be replacing a far cheaper battery a little sooner than I otherwise would or will the overcharging cause the replacement battery to fail quickly and perhaps eliminate any savings from not going to the dealership? Thanks

 

Post #181 on this thread


https://www.clublexus.com/forums/rx-...dealer-13.html

 

Replaced mine in Jnauary when it wnet out during ice storm. Did not lose any settings except clock. I also made sure the transfer only took about 30 seconds

 

Well my turn to get a new battery. Sluggish to start, weird errors on dash (which went away after a minute, probably when voltage got up to a usable point). I’ll put it on a charger overnight then go to Interstate in the morning. 3 year old battery but the Arizona heat is brutal.

 

Batteries don't like heat. Let us know how you make out.

 

Okay, I got my new battery, other than having to turn my air conditioner back on, it did not appear to lose any settings.

However, I have a new problem: with the old battery, just before its last cranking I got an error message upon startup that Parking Assist was unavailable, complete with a Check Engine light. The light and warning symbols went away after driving a few minutes, but when I backed up, no parking assist lines appeared on the rear view camera (just the fixed blue lines). New battery was installed, but I still do not have rear parking assist, even though all cameras appear normal…I get the beeping from too close, and I can toggle PKSA on and off on the dash, but it is not working.

edit: Solved! Low battery evidently causes it to lose the steering wheel calibration needed for the parking assist. I turned steering wheel hard left, then hard right, and put it in reverse, and voilà! My yellow guidelines are back! Whew, I was worried something expensive had fried.

edit #2: FWIW, the Interstate battery guy said I should get the 24 month battery and not the 36 month; he said the more expensive battery was better suited for cold weather, but its plate thickness wasn’t optimal for Arizona heat. He also pointed out an insulation piece around the old battery, which he said Lexus installed to assist in cold climates like Canada and Alaska; he said it should be removed for hot climates (which he did) because it contributes to battery overheating. Total price including tax and $20 install was $244.

 

Thanks for the update. Everything sounds good!

 

Hi All,

Just signed up, first post here. Purchased a new-to-me '21 RX350. Has factory battery. I will be swapping it out as it's 4 years old and I live where it gets nasty cold (and hot too). I've read some conflicting info on the battery type being an EFB (Enhanced Flooded Battery). What are people doing on battery replacements for these vehicles? Staying with an EFB (if that's truly what they are) or upgrading to an AGM?

Thanks.

 

I just bought a new Interstate battery, the standard kind with the 24 month warranty, for about $240 installed with tax. The guy at the Interstate Battery place said that version was better able to handle the Phoenix heat than the more expensive 36 month warranty version. They didn’t even mention upselling to the even-more-expensive AGM version. My take is that the standard battery is just fine for our needs.

 

Thanks for the input. The more I read, the more it appears that these vehicles are using EFB (guessing due to the amount of electronics/sensors onboard). Seems a standard flooded lead acid battery would suffice as these vehicles do not have auto start/stop annoyance built in.

 

I believe there is already an extensive thread in this forum with numerous recommendations and reviews for car batteries. Use the search feature.

 

After getting many reports of strange transient warning lights from the wife, I replaced our original battery with an AGM from Costco. No trouble since.

I wasn't a fan of having to remove trim in order to replace the battery, but all cars are like that now. At least the re-installation was smooth and I got to do a little bit of cleaning.