Battery Dying
11-10-20, 01:53 AM
#16
What? Your car's electrical system is 12V nominal. You measured 12.16V -- how is that "26%"? You need to measure cold cranking amps (CCA), not voltage, to determine the charge.
Last edited by dibl; 11-10-20 at 02:13 AM.
11-10-20, 07:55 AM
#17
Rookie
Thread Starter
There are many websites that explain all this. For example, see https://www.centurybatteries.com.au/...g-battery-life
11-10-20, 11:08 AM
#18
OK. I wrote "system", meaning the voltage required by the lights, window motors, starter motor, etc., however, I take your point about the fully charged battery voltage, and the maintenance tips.
However, the fully charged battery on my riding mower will measure 12.6V, probably. But it won't start my car. Its the amperage that spins the engine, using the starter motor. I remain very skeptical that your car battery is performing as per its CCA rating, even if it is possible to charge it to 12.6V.
However, the fully charged battery on my riding mower will measure 12.6V, probably. But it won't start my car. Its the amperage that spins the engine, using the starter motor. I remain very skeptical that your car battery is performing as per its CCA rating, even if it is possible to charge it to 12.6V.
11-10-20, 12:26 PM
#19
Rookie
Thread Starter
OK. I wrote "system", meaning the voltage required by the lights, window motors, starter motor, etc., however, I take your point about the fully charged battery voltage, and the maintenance tips.
However, the fully charged battery on my riding mower will measure 12.6V, probably. But it won't start my car. Its the amperage that spins the engine, using the starter motor. I remain very skeptical that your car battery is performing as per its CCA rating, even if it is possible to charge it to 12.6V.
However, the fully charged battery on my riding mower will measure 12.6V, probably. But it won't start my car. Its the amperage that spins the engine, using the starter motor. I remain very skeptical that your car battery is performing as per its CCA rating, even if it is possible to charge it to 12.6V.
Last edited by rx20info; 11-10-20 at 06:38 PM.
11-10-20, 06:35 PM
#20
Rookie
Thread Starter
Driving the vehicle for 30 minutes with all accessories off for at least 10 miles above 30 MPH will maintain the battery’s charge
Not really a practical solution.
First, you now have a new job: using your car as an expensive battery charger. What is your time worth?
Next: if the car is not driven we can assume it's dead cold? Starting and running the car at ambient temperature is the worst engine wear it will ever see. Ricardo discovered 100 years ago that the combustion process etches away the cylinder wall every time the piston stops, and it's far worse when it's cold. The damage is visible to an electron microscope after only a few hours.
Last, when you start the car cold, the first combustion energy used is wasted by bringing that 600 lb. engine and transmission up to operating temperature. A V8 at 40 degrees F may use 1 gallon of gas in the first mile. With very rich mixture, the partially burned gas is now water vapor and sulfuric acid in your oil.
Get a Schumacher battery tender.
Not really a practical solution.
First, you now have a new job: using your car as an expensive battery charger. What is your time worth?
Next: if the car is not driven we can assume it's dead cold? Starting and running the car at ambient temperature is the worst engine wear it will ever see. Ricardo discovered 100 years ago that the combustion process etches away the cylinder wall every time the piston stops, and it's far worse when it's cold. The damage is visible to an electron microscope after only a few hours.
Last, when you start the car cold, the first combustion energy used is wasted by bringing that 600 lb. engine and transmission up to operating temperature. A V8 at 40 degrees F may use 1 gallon of gas in the first mile. With very rich mixture, the partially burned gas is now water vapor and sulfuric acid in your oil.
Get a Schumacher battery tender.
03-04-21, 06:46 AM
#21
Driver School Candidate
Battery Dying
Hello -
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
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GargoyleRX (12-28-22)
03-04-21, 08:36 AM
#22
Advanced
Hello -
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
Leave them the car overnight and tell them to start the car the day after.
03-04-21, 09:31 AM
#23
Lexus Test Driver
How often is Mom driving the new car??
03-04-21, 01:24 PM
#26
The following copied from a Lexus PDF:
Lexus Vehicle Battery Maintenance
Lexus Vehicle Battery Maintenance The primary battery in your Lexus vehicle needs to remain fully charged to start and drive your vehicle. If not used regularly, it may reduce its performance and life. In the worst-case scenario, it can even leave you stranded. There are conditions including how long it is stored without being driven, as well as parasitic draw that can impact the battery’s available charge. Because of these factors, battery maintenance is required to ensure proper operation and optimal battery life.
Under the current COVID-19 environment, some people may not be driving their vehicles for long periods of time. There are three methods of battery maintenance:
1. Driving the Vehicle/Starting the Engine This is the easiest method. The vehicle is used weekly after non-use. Driving the vehicle for 30 minutes with all accessories off for at least 10 miles above 30 MPH will maintain the battery’s charge. If you are unable to drive the vehicle, start and run the engine in an open-air environment for 30 minutes with all the accessories off.
2. External Battery Charging Connect an external battery charger (also known as a battery “tender” or “trickle charger”). This device hooks up to your car battery on one end and plugs into a wall outlet on the other. It delivers enough electrical power to prevent the battery from discharging. For instructions on how to safely connect a battery charger, contact your Lexus dealership. Your local Lexus dealer may have an external battery charger available for purchase at a nominal cost. Alternately, you can purchase an automotive battery charger online.
3. Disconnect the Battery Cable Parasitic draw or parasitic drain is a term for an electrical component consuming electricity when the vehicle is not used, even after the vehicle has been shut off. The average vehicle can have as many as 50 computers that all use small amounts of electricity. Over time, this can cause the vehicle's electrical system to function improperly and the vehicle may exhibit the following symptom: a persistently dead battery. To reduce parasitic drain on vehicles in storage for a week or longer, the negative (-) black colored battery cable may be disconnected to eliminate the battery discharge. Note, when the negative (-) battery cable is reconnected, you will need to check and reset electrical components such as the clock, radio settings, seat memory, etc.
Lexus Vehicle Battery Maintenance
Lexus Vehicle Battery Maintenance The primary battery in your Lexus vehicle needs to remain fully charged to start and drive your vehicle. If not used regularly, it may reduce its performance and life. In the worst-case scenario, it can even leave you stranded. There are conditions including how long it is stored without being driven, as well as parasitic draw that can impact the battery’s available charge. Because of these factors, battery maintenance is required to ensure proper operation and optimal battery life.
Under the current COVID-19 environment, some people may not be driving their vehicles for long periods of time. There are three methods of battery maintenance:
1. Driving the Vehicle/Starting the Engine This is the easiest method. The vehicle is used weekly after non-use. Driving the vehicle for 30 minutes with all accessories off for at least 10 miles above 30 MPH will maintain the battery’s charge. If you are unable to drive the vehicle, start and run the engine in an open-air environment for 30 minutes with all the accessories off.
2. External Battery Charging Connect an external battery charger (also known as a battery “tender” or “trickle charger”). This device hooks up to your car battery on one end and plugs into a wall outlet on the other. It delivers enough electrical power to prevent the battery from discharging. For instructions on how to safely connect a battery charger, contact your Lexus dealership. Your local Lexus dealer may have an external battery charger available for purchase at a nominal cost. Alternately, you can purchase an automotive battery charger online.
3. Disconnect the Battery Cable Parasitic draw or parasitic drain is a term for an electrical component consuming electricity when the vehicle is not used, even after the vehicle has been shut off. The average vehicle can have as many as 50 computers that all use small amounts of electricity. Over time, this can cause the vehicle's electrical system to function improperly and the vehicle may exhibit the following symptom: a persistently dead battery. To reduce parasitic drain on vehicles in storage for a week or longer, the negative (-) black colored battery cable may be disconnected to eliminate the battery discharge. Note, when the negative (-) battery cable is reconnected, you will need to check and reset electrical components such as the clock, radio settings, seat memory, etc.
Last edited by RGSW; 03-04-21 at 01:35 PM. Reason: Original URL would not come up.
03-04-21, 01:39 PM
#27
One possibility is excessive parasitic drain. All cars today have a small amount of battery drain while they are shut off. That current should not exceed .05 amps. You need to have someone check it for you. It is also possible you have a bad battery. It happened to me some years ago I bought a brand new battery and it was junk from day one.
03-04-21, 08:07 PM
#28
Instructor
I suspect a defective battery. If your Mom is driving twice a day, even briefly, 10 minutes in each direction, that should be enough to keep a new battery charged up. If all the dealer did was attach a volt meter to the battery, then of course it would show good. Find out if they are checking the acid with a hydrometer, which would reveal a dead cell. Another test is the one that puts a load on the battery for a specific amount of time. I don't recall the name of the test. BTW, what are the symptoms of the battery dying every few days? Slow cranking? Clicking when pressing the start button? Are you parking outside in sub-zero temps? I drive my Avalon once a week on a short errand and the battery is ok. It's new. Hope this helps. Ray A.
PS By any chance, is she leaving the door ajar? Just an afterthought.
PS By any chance, is she leaving the door ajar? Just an afterthought.
Last edited by raylor4; 03-04-21 at 08:10 PM.
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bamalam (03-05-21)
03-05-21, 03:29 AM
#30
Driver School Candidate
Faulty Battery
Hello -
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
my mother just bought a new 2021 RX 350 in December. After about a month the battery started dying every few days. I just assumed that she was leaving something on that was draining the battery but after boosting it a number of times I'd check and see nothing left on. It was brought to the dealer and they said that everything is fine. Just wondering if anyone else has had this problem or may know of something that's causing this to happen. Thanks!
The following users liked this post:
exonw (03-13-21)