When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I found the attached pages in the manual which suggests we need to put distilled water in the 12V battery. I haven't seen or done this in any car I've owned for 30+ years. Boats and golf carts yeah but all the cars I've ever had came with maintenance free batteries. Why wouldn't Lexus have used at least a sealed lead acid battery? I'm puzzled by this.
Do we really need to add water to these 12V batteries? Manual re 12V battery.
pic of our RZs 12V battery.
I think they're maintennce free and sealed for life in the same way they say transmissions are. In other words it's possible they'll lose some water over time and, if possible, topping them off with distilled water might extend their life. You should be able to see the levels through the sides, and so if a battery has removable caps then by all means top it up. Personally I've never bothered.
I haven't been able to see the level/levels(?) thru the sides. I tried shining the flashlight every which way last night and I couldn't see any evidence of water levels thru the white plastic.
I don't even know what tool to use to open and check the water thru the vents. A coin didn't work very well and the plastic is easily stripped. I gave up trying. It's also funny that the manual says not to "recharge" the battery in enclosed spaces. Um, isn't under the hood an enclosed space and, um, doesn't the HV battery recharge it? What a strange battery and manual entry. If we don't have to add water every month, it's probably best to leave it alone, huh?
Looking at the bottom right of the picture it suggests that the caps are primarily vent caps rather than top up ones. Of course you could refill via them (if you could remove them), but I wouldn't bother.
12V Battery Needs Maintenance?
