Does anyone know what the current draw from the battery should be with the RX300 turned off? The reason I ask is that I see a blue circle on the battery test window indicating a good battery but the car won't start after being parked for a while and must be jump started.

I tried to measure the current draw with everything off but it blew the 0.5A fuse on my analog meter. I was expecting more like 50mA.

I might need a new battery and I'm not sure how old the battery is since we purchased the RX used. I am concerned however about the draw from the battery. By the way, I had a jumper wire in parallel to the meter at first to handle the startup (rush) current, but as soon as I removed the jumper and all the current was going through the meter, it blew the fuse in the ammeter.

Any info on a normal current draw for the RX300 with everything off would be appreciated.

 

0.5Amp @ 12v => 6wattse
Door ajar courtsey lamp would have popped the fuse.

With so much automation you will be surprized what is ON with just the key in ignition (even at off).

Salim

 

This is 12V DC with High 650 Amps ... You need an "Inductive" adapter that measures the magnetic field of the wire the current is running thru.
Go by an auto store or two and have the battery and alternater checked... They usually do this for free, but get mutliple opinions so your confident with what needs replacing.. Chances are it is the battery...I assume it's the original with the blue dot indicator. .

 

I found the date code on the battery and it was dated 09/07/99. So the battery was the original and about 6 years old. Therefore, I went ahead and bought a replacement battery from Lexus.

For those who may be curious, I found a better meter and went ahead and measured the current draw again with everything off (key out of ignition, all doors shut), and I measured around 580mA. I'm still surprised that it is this high, but I have no idea if this is typical with newer cars or not. Maybe, I'll go ahead and measure it on my ES300 and see how it compares.

Thanks for the replies!

LC1338

 

Battery like tires are generic parts, was there a special reason you went to the delership for a replacement?

Salim

 

Your battery may still be good. Try clean the battery clamp connectors with a wire brush first.

 

It's a long story, but no particular reason really. I'm sure I could have bought an equivalent battery for a lot less from an independent shop.

 

.5 amp draw no more than .8 amps

btw dont use an analog meter. out dated

ive got a snap off meter dvom
the only things that are still on are clock memory and the alarm system

 

not always true. i found that interstate batteries in lexus tend to go bad in about 2 years. but it also depends on where u live. here in chicago batteries tend to last 3 years