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S/O's 1996 Toyota RAV4 would not start and the automatic transmission selector lever would not shift. Radio, power windows and head lights worked fine. Cleaning the connectors helped start up the engine. The interior lights went dimmed before the engine was fully powered up. Is it a signal for a new battery, or is it something else? TiA
Kap
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this is when you pull out your handy dandy digital (or analog) multimeter, and see if the vehicle puts out about 14 volts when it is running, or about 13 volts when it is running and the high beams are on, rear window defroster is on, and the heater and wipers are going.
I could go more into it, but the gist is that when the vehicle is already running, the battery pretty much just takes up space, and adds weight.
Many auto parts store (the big chains that is) can test the battery and charging system, and most are free too. They don't want to sell you a new battery, and have you come back 2 days later pissed off and claiming that the battery is defective, when all along the alternator/voltage regulator was bad. Trust me on this.....I managed an auto parts store for 4 years.
p.s. every person should have a digital multimeter in their toolkit. They start as low as $10 or so. Even the cheap ones work great for basic voltage checks like this. I have 6 digital multimeters, and an analog one. One cheap one in the glove box of every car. The good Fluke 77 stays inside the house
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The current battery is about three years old. So I think it's time for a replacement.
Kap
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Lots of alternators have integrated voltage regulators. Many times one diode will go out and it will sort of work for a couple of months and then you have problems just like this. It could also be a bad connection somewhere or a loose belt.
I have not had a battery last less than 4 years since 1986.
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good point Muffman. I have had an alternator (on an old buick, if you can believe that!) with one of the 6 diodes bad. It would put out a low current at 14 volts, but when it wasn't running, it would pull power from the battery and drain it. That was a bitch to figure out.
That is why the whole system should be checked (hopefully for free).
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Sometimes it's just dirty connectors, or worn cables.
Make sure you've cleaned the connections well and and tightened the cables securely.
Then charge the battery or at least do 20min or more freeway driving, preferably in the daytime.
Getting your charging system and battery tested (under load) should tell you exactly where the problem is.
Having owned only American cars with large batteries, I think 2-3 years is far to short a life span for a good lead acid battery. But I could be wrong wear other cars are concerned.
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all it takes is one good pothole to crack a plate in a battery. That is why they make "truck" batteries for light trucks. They have less plates, but they are thicker. But with todays tighter suspensions and shorter sidewalled tires, cars ride rougher than they did 20 years ago, or even 10 years ago. And a '96 RAV4 will ride more firmly than a '96 Lincoln Town Car.
The most common failure of a battery is a dead cell, and that is usually one of the 2 end cells, and that is usually caused by the battery clamp being pounded on when the battery is installed. Even moderate tapping will weaken it. Remember, the post, and what it is attached to, is just lead
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"Getting your charging system and battery tested (under load) should tell you exactly where the problem is. "
Definitely. 3 years is too short, sometimes this indicates voltage regulator problems. Also check the neg. connections to the engine block/frame.
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Three years is an awfully short lifetime for a battery. What is the warranty level on the battery? It'd have to be an el cheapo junko to fail in that short a time period.