dead car : battery / something else ?
Thread Starter
Driver School Candidate
Joined: Aug 2012
Posts: 2
Likes: 0
From: CA
dead car : battery / something else ?
Hi All,
Faced a dead battery and below are the steps I followed
Car did not start in evening as if battery was dead.
Called road side for a jump start.
They tried to jump start but no use.
So, instead of giving the possitive of external battery to possitive of car battery, he gave it to possitive terminal sitting in the fuse box of the car.
Car came to life now.
Drove around a bit so that alternator can charge the car battery
Got home; turned off the car and tried to turn it back on.
No internal lights; nothing;car dead again
Any help on where to start trouble shooting or what could be wrong will be really helpful.
Thanks in advance
Faced a dead battery and below are the steps I followed
Car did not start in evening as if battery was dead.
Called road side for a jump start.
They tried to jump start but no use.
So, instead of giving the possitive of external battery to possitive of car battery, he gave it to possitive terminal sitting in the fuse box of the car.
Car came to life now.
Drove around a bit so that alternator can charge the car battery
Got home; turned off the car and tried to turn it back on.
No internal lights; nothing;car dead again
Any help on where to start trouble shooting or what could be wrong will be really helpful.
Thanks in advance
Instructor
Joined: Apr 2001
Posts: 934
Likes: 198
From: N. CA
Most like your battery is too old or defective that it won't charge anymore.
Go to Costco and buy a new battery and drive it for a day. If it is OK, then it is just the battery.
If after a day of driving the car won't start with the next battery, then it is most likely the alternator.
Go to Costco and buy a new battery and drive it for a day. If it is OK, then it is just the battery.
If after a day of driving the car won't start with the next battery, then it is most likely the alternator.
Thread Starter
Driver School Candidate
Joined: Aug 2012
Posts: 2
Likes: 0
From: CA
Yes, the road side did not test the battery.
1 more question regarding the above quote -
so, when I started driving my car, for the first 2 mins or so, the brake light, the vsc, the maint reqd light were coming on .... once I revved up the engine, the lights went off, things started looking normal again....would this rule out alternator problem ?
I will, of course, go get the battery tested and update what corrects my issue.
Thanks again to everyone
Lead Lap
Joined: Jan 2014
Posts: 694
Likes: 1
From: Rep of South Africa
A Lexus will light up a million warning lights for you, if the alternator is going south. I would've dashed out long ago to buy a new battery. If they get long in the tooth, batteries develop internal shorts and start behaving in a way which will baffle a magician. On the other hand, I've never heard of a Lexus which you have to rev to get warning lights to go out. So one cannot rule out that you have a negative earth cable that's not making the good connection it is supposed to do or for that matter any other relevant wire that is not making good contact.
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Pole Position
Joined: Sep 2006
Posts: 3,054
Likes: 103
From: Sacramento, California
If the battery has a shorted cell, it can load the alternator down causing a low voltage condition, hence the lights.
After replacing the battery the terminal voltage should read 13.5 to 14.5 volts with engine running. With engine off the battery should read 12.6 volts. If the voltage while running is less than 13.5 with new battery the alternator is probably toast.
After replacing the battery the terminal voltage should read 13.5 to 14.5 volts with engine running. With engine off the battery should read 12.6 volts. If the voltage while running is less than 13.5 with new battery the alternator is probably toast.
Lexus Champion
Joined: Oct 2006
Posts: 1,717
Likes: 10
From: Dallas, Texas
If a battery fails, replace it. I don't understand trying to squeeze more time out of a battery that has let you down even once. If it's under warranty get another one, if it's old spring the hundred bucks and replace it
Instructor
Joined: Aug 2018
Posts: 999
Likes: 228
From: NM
Racer
Joined: Sep 2014
Posts: 1,811
Likes: 91
From: Scottsdale, AZ
inded i concur with others; its most likely the battery; but if u see the battery light come on while the vehicle is running then thats a sign that the charging system is failing which is time to have the alternator looked at.
Rookie
Joined: May 2014
Posts: 47
Likes: 2
From: FL
Battery going dead
Dear iMSQ, matts6887,and DennisMik, I have checked all those things. It is a brand new battery, there is no corrosion, and I have had the car checked by 2 different auto electric shops.
It still goes dead if I let it sit for a few days. I will check the 'seat set' buttons again, but I looked at them and they appear OK. JC
It still goes dead if I let it sit for a few days. I will check the 'seat set' buttons again, but I looked at them and they appear OK. JC