Hi all,

I just bought my wife a used 08 RX400h with 69K on it. I immediately took it to a Lexus dealer for an inspection. They found 2 things wrong with it: dirty air filter and a low (210 cca) 12v battery.

I have read and searched the battery threads. Our truck hasn't failed to start but must have sat around for little while before we purchased it.

I have the following battery questions:

Does 210 ccas mean the storage capacity of the battery is gone or is it temporary reduced because the truck had been sitting?

If I buy a load tester, will it show me cca?

I have read on various threads that the Yellow Top Optima deep cycle batteries is a good option but don't understand why if the 12v is constantly being charged vs. the battery is almost completely discharged before being recharged. I would think no deep exercise would be bad for a deep cycle battery.

Finally, has anyone put a bigger 12v wet cell battery in their RX400h or maybe even one out of a Rx350?

Thanks...

 

First, any measurement of cca without some serious equipment is not necessarily going to be accurate. For techies, here's likely far more than you wanted to know:
http://batteryuniversity.com/learn/a...d_cranking_amp

There are those who swear by Optima batteries, and there is some good reason for them to do so. But, in our 400h's, there isn't all that good a reason to get one in my opinion.

Fitting a larger battery requires making a bigger space for it. That's likely more work than it's worth.

My suggestion would be to drive the car a few more days, and then go to Autozone and have the battery load tested. If it fails or is even just not quite what it should be, get a new battery then and there. If it's good, well, use your judgement. If you keep it and you experience even a one-time case of the ready light not coming on right away, consider that a strong hint. Keep in mind that only a modest percentage of owners have reported battery failures here.

 

I now have access to a friend's load tester and hydrometer. Is the OEM battery sealed in way that we can not access the cells to use the hydrometer?

What load tester reading should I be looking for when the battery is fully charged?

 

Yes the cells can be accessed. But why bother, just get a new battery and be done with it....

 

OK, took your advice and got a new 51R battery. Since I don't have a owners manual yet, I looked at the online manual. Under battery, it doesn't list any procedure to initialize anything. The only thing I was able to find is the initialization procedure for the windows.

Is this the only thing that needs to be done after disconnecting/reconnecting the 12v battery?

Thanks...

Neil

 

You may also want to initialize the sunroof (slide open/close, not pop-up) the same way you did the windows.

 

Since initialization, the driver's door window does not function in auto. It does not one touch roll all the way down or roll all the way up. The other windows do.


I assume I have to disconnect the battery again to reset or is there something else going on?

 

Have you sign up with Lexus online as the new owner of the 400h ? You should beable to get to the owners manuals online whenyou do.

 

Yes, I have signed up at mylexus.com and have ordered an owners manual. I have searched the online manual and the reinitialization procedure I found was just related to the windows. I sued the procedure and now the drivers window does not go into auto mode.