ReinyDey

Hello,

I do not drive my 2001 RX 300/LTD much so it can sit for days at a time. I had it jumped mid-December and immediately drove it to an auto store, since this was not the first jump due to the dead battery.

Beforehand though, I did some online research for causes of a dead battery and had them check the alternator, starter, and battery (Diehard) installed early 2008. The tests produced these results.

Battery Test:
Volts: 12.67
Rating: 572 CCA

Starter Test:
Cranking Normal
Voltage: 11.08v

Charging System Test:
No problems
No load: 13.94v
Loaded: 13.92v

They charged the battery for 30 minutes after testing and sent me on my way a semi-happy camper . The consensus: I do not keep my battery charged which is why it dies after a week of non-use. Then last week, you guessed it--the battery died again, and now, once again it sits in the parking lot dead. So, before I have it jumped, yet again, I am desperately hoping you can provide some insight of your own.

It is inevitable that the car will sit for long periods; therefore, how can I stop the battery from discharging in the most cost-effective and efficient way?

a. Is Battery Tender a solution even if my car is not housed in a garage?
b. Disconnect the Negative Terminal when I get home?
c. Something else?

Thank you in advance.

Big Joe

Do you have a keyless entry? My battery was going dead and found out if the key is within 10 ft it will send out search signal and kill the battery. Just something to think about. Joe

salimshah

If you dont drive enough, you should put a charger on it once a week. A new battery can sustain itself but past a year or two, it needs the overnight charge.

Disconnecting the battery might extend the time between charge, but it resets so many things and the aggravation of once a week to charge is relatively less.

Salim

ReinyDey

Hi Joe,

I have a keyless entry, but it is way outside 10-ft. radius of the truck.

ReinyDey

Hi Salim,

I can see how disconncting the battery can create it's own frustrations. Can you recommend a viable charger for my situation?

Thank you,

lexus114

just a common battery charger from Sears etc. Put it on a 2amp charge all night.

sktn77a

iTrader: (2)

Take it somewhere else to be checked. There's a problem somewhere! It's either a bad battery, bad charging system or a slow discharge in the car. Do you have any aftermarket electrical items installed? My bet is still the battery - I've gotten less than 3 years out of my last two (72 month) Diehard batteries. Luckily, the were exchanged under warranty. But they definitely don't make 'em like they used to.

code58

Once again sktn is on the mark. Your last statement is on the mark. They would have no problem making a battery that would last 10 years or longer- but they wouldn't be in business long now would they? Does anyone actually believe a battery with a 100 mo. warranty will actually last 100 mo.? Only the rare person who really treats their battery right will get 50 mo. out of that 100 mo. battery. My DIL's Costco battery (that I bought and installed) with 36 mo. FREE replacement and 100 mo warranty just developed an open cell with 40 mo. on the battery. I have 2 expensive testers and test my batteries every 2-3 mo and the Costco battery in my wife's car which is 2&1/2 yrs old is getting lower all the time. Now load tests at about 12.2 V and the car is driven EVERY day, charging system is GOOD. There are no more quality batteries on the market that I know of since GNB (Gould National Battery) sold to Excide in about '03. You can't tell by how it starts, it's condition. You have to load test it! What I do if I have a problem like that (going dead often) is fully charge with a smart charger (that will tell me something in addition to KNOWING it is properly and fully charged), then remove the bulb from the under hood light and put an "amp clamp" on the + cable to see what the draw actually is (after making sure all KAL memory has had a chance to go to sleep). Only then can you some kind of idea what you're dealing with. This is why I have a ton of electrical testing equipment (in addition to the fact I used it in my work before I retired). I have both an OTC "conductance" tester $500.+ as well as a 1000 amp carbon pile tester. I use the OTC tester routinely, but still have greater faith in the carbon pile tester when push comes to shove.

code58

RD- I personally like to see the charge rate a little higher than that, unless it was done at idle, but there is certainly nothing wrong with those #'s. Even the charge rate is within most all manufacturers guidelines. At about 15-1600 RPM it makes me really happy to see about 14.2-14.3V.

salimshah

There are 3 types of chargers[listed cheapest to most expensive]:

1. Float or trickle chargers. Do not have lots of oompf and can charge good batteries [can not charge a discharged battery].

2. Regular chargers. May have options for 6v or deep-cycle batteries. You have to let the battery charge up before attempting to start.

3. Chargers with boost. They can help you start with the charger.

Select one that suits your current and future needs.

Use the charger in ventilated area where there is NO spark or open flame. Connect the + at the battery.
Connect the - far away from battery.
Plug in the charger.

For removal reverse the procedure.

The above will ensure if there is any spark it is away from the battery.

Salim.

ReinyDey

Hi Keith,

I was hoping that was not the case and I honestly do not have a lot of confidence in workmanship coming from shops in my area (too many horror stories), so I am at a loss as to where to take my truck; but, I will figure something out when and if the battery turns out not the be the problem. I haven't had enhancements done to the vehicle and coming to think of it, not one of my batteries have lasted it's warranty period in the Lexus.

Thank you,

HarrierRX300

This is exactly the same situation for me. I started a thread I think last week about getting a new battery, either a Lexus battery or a Toyota battery. My plan now is to charge the battery, bring it to a mechanic and perform a tune up, change brakes, resurface rotors, flush brake fluid, transmission fluid, etc., and while they're at it, check the battery charging system. When they're all done, I'll buy either a CostCo battery or a Toyota battery. I've heard stories of mechanics leaving the door open so the battery is dead the following day. I'd rather have that peace of mind that I have a new battery after all the mechanics are done to the car prior.

salimshah

Either get a new (strong) battery that will be able to sustain more discharge than charge for a while, or make arrangements to charge the battery.

Once the new battery is not so new, you get in to the situation described above. Charging system checks out ok, and once the battery is charged it can start the vehicle. A quick load test can also check out ok. I am not sure if there is a repeat load test to check sustained supply capacity.

Salim

ReinyDey

Hi Lexus,

Thank you for the suggestion. I will look into this.

lexus114

That`s what I do any way`s. Work`s for me. Unless it`s a definite battery problem,then what the other`s suggested might come in to play.