How to safely jump-start your dead car battery PLUS, is it the alternator or battery's fault?

Okay, so I'm getting ready to have this teen driving experience, and I'm really excited

about it.

I'm getting a lot of phone calls, I'm getting a lot of reservations.

It's next week, it's on Tuesday, the March the, what is that, 24th from 6 to 8.

And it has generated some interesting comments in the mailbag that I want to share with you.

You know, a lot of adults say, I wish I'd had that when I was 16, because I didn't know anything.

Well, you know, I'm reflecting on what did I know when I was 16, as far as cars.

My dad was a new car dealer, Chevrolet dealer, and let's see, did we have, no, we didn't have Mazda at that point.

So we're a single point Chevy dealer in Granville, Tennessee.

The only place that I'd ever worked in the dealership was in the detail department, washing cars.

And at 16, I was delivering parts as well.

So I knew how to drive a manual because the parts truck was a, I don't remember what year, but it was a Chevy love truck.

Do you remember those?

They were built by Isuzu for Chevrolet, or for General Motors.

And for Isuzu as well, they had a version of it.

I don't know what theirs was called, but they had a manual transmission and I delivered parts in it.

So I did know how to drive a manual.

Most 16 year olds today don't, you know why?

Because they don't have to.

They don't build cars with manual transmissions anymore.

I'm trying to think, well, we sell the Mustang.

No trucks that we sell have manuals.

Not even the new little Ford Maverick.

All of them are automatics.

You know why manuals went away?

Because automatics are more efficient from a fuel saving standpoint.

It used to be that way.

Back in them old days, the manuals were more fuel efficient because the automatics only had two.

Two or three gears.

Two or three speeds, that's it.

But when they came up with a fourth speed and then they came up with lock up torque converters

and then added a fifth speed and a sixth and a seventh and eighth, we have a 10 speed now.

In my F-150, it has a 10 speed automatic.

When you've got that many gears to go through as you're accelerating and decelerating and so forth,

you can wreak some efficiency out of an engine.

So that's why manuals went away.

We just sold our last manual a few weeks ago.

There went another alarm.

This is live radio, folks.

Yeah, when the Nissan Versa stopped making manuals, that was it.

I take that back.

The Nissan Z still has a manual and the Ford Mustang.

And I think that's it.

It's hard to believe that a Chevy Corvette no longer has a manual transmission.

I ordered my new Porsche 911 in 2024 with a manual.

People said, why are you doing that?

I said, because I like, I don't know, it's just I'm more involved in what's going on with the manual.

I feel like I can control the car better.

Maybe I'm wrong because no race cars have manuals.

I mean, NASCAR race cars do, but you look at Formula One, you look at the Le Mans with all the prototype cars and Porsches and Lamborghinis.

All of those have something called a dual or triple clutch automatic with paddle shifters.

You know, they have these little paddles on either side of the steering wheel and one goes up and the other goes down.

And you can get around a racetrack a whole lot faster with that than you can with a manual because a human cannot push in a clutch shift gears as quickly as these paddle shifters can get you to a different gear.

So anyway, I wanted to get back on some of the subjects in the mailbox because, you know, one of the most common things, one of the most common emergencies.

It's not really an emergency, but it can be that a lot of people have is that their car won't start.

They hit the ignition and nothing happens.

It goes wrong, wrong, wrong, you know, makes a noise or it does nothing click, click, click.

So what does that car need?

It needs to be jump started.

And what is the process for doing that?

Well, I'm going to try to give you one.

If you want to get at your pen, pencil, crayon, whatever, I'm going to tell you a simple way to remember this.

Are you ready?

Okay.

There is a sequence that you're supposed to hook the cables up.

And if you don't do it right, you can damage the electronics on your modern car.

You don't want to do that because remember what I say about self inflicted wounds?

If you damage the electronics on your vehicle because you jump started it incorrectly, that $3,000 bill at the car dealership is not going to be covered under warranty.

So you better hook up the cables correctly.

Really, you need to pull the owner's manual out and see if they have any precautions in there.

They may say, don't do it.

And in that case, you call the wrecker or the rollback and have them come get your car.

But if they say, go ahead, you know, go ahead and jump start your car.

Here's the sequence.

Red?

Okay, so jumper cables have a red clamp on one end, red clamp on the other, black clamp on the other.

There's my alarm again.

Black clamp on one, black clamp on the other.

Okay, so you got on each side a red and a black.

One's positive, one's negative.

Red is positive.

It's marked on the battery as well.

Okay, there's a little plus sign beside the post that's positive.

And then there's a little minus sign beside the post that's negative.

You got that?

See, sometimes I get ahead of myself.

Some people may not know that.

So you connect red to the dead car, then red to the good car, the one that'll start.

Then you connect black to the good car.

And then you connect the final black.

Does it go on the battery post, the black battery post, the minus?

No!

It goes to an unpainted metal surface on the engine block or on the frame of the dead vehicle.

There's a good reason for this, because usually that last connection will create a spark.

Are you going to get electrocuted?

No.

But if you connect it to a battery that has a crack in it, that has leaky battery acid coming out of it,

it's not the acid you're concerned about, it's the fumes.

Those fumes can ignite and the battery will blow up in your face.

And you will have sulfuric acid all over you, which is not a good thing.

Do you see why you might want your kids to know how to hook these up?

Oh, one other precaution.

By the most expensive cables you can find, they have better clamps, they have thicker wires,

and they'll work when it's really, really cold and your battery is really, really dead.

Okay, what else?

Oh, you've got to start the vehicles then.

So first you start the good vehicle and let it run for a minute or two.

And then you try to start the dead vehicle.

And sometimes nothing will happen, probably because you need to check your connections.

So just grab the clamp, move it around on the battery cables, make sure you do it in the same sequence when you put them on.

And then go back and try it again.

Then it will start to turn over and it will probably start at that point.

But if it doesn't start and it's trying to start, then just wait.

Just wait.

Go to the good vehicle and rev the engine some.

That'll send some extra current over to the bad one.

Wait about two minutes, then go over and start and it'll probably start then.

So that's the sequence.

And then you reverse that sequence to take them off.

Because again, you don't want to create any unusual sparks.

A couple other things don't ever let the clamps touch one another,

especially after one or more have been connected to the vehicles.

Keep those clamps separate from each other.

Again, you're creating sparks.

Could get a little shock if you're not careful.

So that's all you need to know about jumpstarting a car.

And if you didn't catch that, then if you're listening to the podcast, just back it up.

If you're on the radio station, you're out of luck unless you go and download the podcast

and you can listen to it again.

You know, I'm not the only source for this information,

but pretty much everything that you ever see about jumpstarting a car is going to be right exactly like that.

Now, the next subject that I'm going to talk about, a little bit more electrical system stuff.

There's a lot of people that just really don't understand their electrical system on their vehicle.

And it's very important to have some kind of a basic understanding

so that if you have a problem with your battery or your alternator,

you know what they're talking about.

And I'll cover that in just one minute.

Okay, I am back from the mailbag.

Hey, Lenny, love your show.

Got a question.

I just bought my second new battery in the last 30 days.

I took the battery back to the auto parts store and they tested it.

They said they couldn't find anything wrong with it, but gave me a new one anyway.

Now it's dead and I'm having to jump the car off.

What's wrong with my car?

And the answer is you've got a bad alternator.

It's not putting out enough electricity to run all of the things that need electricity on your vehicle

and provide enough current to your battery to recharge it.

See, the battery starts the car, the alternator keeps it running.

It's basically the power plant, the alternator is basically the power plant of the vehicle.

So the battery is sitting there and it's got energy stored in it, okay?

The alternator doesn't store anything, it just generates power.

So the battery starts the car, once the car starts, the belt starts turning and it turns the alternator.

There's a little pulley there and the alternator starts putting out power.

Battery goes to sleep.

It just sits there and gets recharged if it's a good battery and a good alternator.

If it's not a good alternator, then the battery is going to fail.

But see, the alternator powers the lights, the radio, any powered accessories, power windows, power door locks, a sound system,

but it also powers all the computer systems on the car.

Now what causes failure to an alternator is just internal wear and tear, you know, bearings, brushes, diodes.

Typical alternator is going to last about 100 to 150,000 miles.

The battery is going to last three to five years.

What kills battery life, let me get back to the battery just a second.

What kills the battery is heat.

Really the cold weather doesn't do it.

Batteries like cold weather.

They just don't like heat.

Another thing is a lot of short trips.

If you just kind of go around town and, you know, you might drive five miles one day and ten miles the next day and just little teeny short trips.

It's never really enough time for your battery to fully recharge after it starts your vehicle and that can be very taxing on a battery.

You can also have parasitic drains.

This is where I tell people, stop leaving your keyless remote.

You know, these modern cars don't have keys.

They have these little remotes.

Don't leave it in your car because when you do that, some of the modules in the car will remain active and don't go to sleep.

And when they remain active, they're creating a draw on the battery and it will drain it over time.

So don't leave your remote keys.

You know, if you have a starter button, you don't leave that in your vehicle.

Even if you don't have a starter button, if you have a key that you can unlock the doors with the push of a button, that will drain it as well.

So don't leave those in your car.

A lot of people say, well, I don't. Who leaves their keys in your car?

My wife. She does.

I have to chastise her occasionally.

Okay, and then the final thing is just, you know, when the car sits too long and it's not being used.

But a battery light should come on when the voltage amperage is too low and it's not generating.

It's not regenerating.

Okay, so let's get back to the alternator.

Why do they fail?

Well, like I said, internal wear, bearings, brushes, diodes, a bad or a loose belt.

Because remember I said a belt is what turns the pulley on the alternator and that's what makes it work.

And if the belt gets loose and it does, those things are adjustable.

And on most vehicles, modern vehicles, they have something called a belt tensioner that's designed to keep the proper tension on that belt at all times.

Used to you had to, you know, adjust them.

You had to put a wrench on a bolt, loosen it, pull the alternator over so it would tighten up the belt, then tighten down the bolt and the nut.

That's what you had to do.

Now they have these tensioners.

Well, guess what? Tensioners lose tension over time.

And another thing, like I said, is the belt just wears out and that will cause the alternator to stop generating electricity the way it's supposed to.

Okay, also a bad battery forces the alternator to work harder.

It's weird that a bad battery can kill a good alternator.

So you may not have a problem with your alternator, maybe your battery, or you might have a perfectly good battery and the alternator is failing.

I just want you to understand that there's two pieces there that make the charging system, the electrical system, work.

And see, now you know the rest of the story, as Paul Harvey used to say.

Okay, what else? Well, you need to know the warning signs, I guess, of an alternator that's going bad.

What do you think it would be?

It would be a warning sign.

That's right, your headlights, they're getting dim.

When you accelerate, the headlights brighten up, but when you take your foot off the gas pedal or you're coasting, the headlights go dim.

You've got alternator problems, or a belt could be a loose belt.

Let's hope it's a loose belt.

Okay, also a battery warning light could come on.

That doesn't necessarily mean your battery's bad.

It could be your charging system is not working the way it's supposed to.

A dim, or like I said, dim lights, flickering lights, slow power windows, or the car just stalls when driving.

Again, the alternator is the power plant of the car.

You thought the engine was, didn't you?

The engine's important, but from an electricity standpoint, the engine doesn't do squat, except it does turn a belt.

That's its only role.

But if the alternator is not generating enough electricity, the car will die, because it requires electricity to fire off the spark plugs, among other things.

Fuel pumps, fuel injector systems, you know, all of that requires some degree of electrical input.

So you remember the guy who started all this conversation about batteries and alternators?

Yep.

A dead battery, even after a recent replacement, can be caused by a faulty alternator, or a loose belt, right?

So if you go into a service department, and you tell the service advisor that, yeah, my car is having to jumpstart it frequently,

and I don't know whether it's a loose belt, or maybe my alternator's going bad, they're going to look at you and say, wow, I'm impressed.

Have you been listening to that guru guy?

And you could say, yes, I have.

Thank you very much, and you should too.

Okay, I'll be back in just one minute.

Okay, what other problems can we solve?

Oh yeah, I got this one.

I mentioned on the show, I think it was the last one, that the proper pounds per square inch PSI for your tires, as far as the air.

We're talking air now.

You find that on a sticker inside your door jam.

And I was called to task on that.

I had a, well, he texted me.

He said, what about the stamp on the tire?

And I said, well, that's not really what he sounded like.

That's just the voice I use.

You know, there is a stamp on the tire.

That's the maximum PSI, okay, for that tire.

That's not what the factory recommends.

Now, if you have changed the size of your tires, you know, if you go out and buy a used car, one of the things that I'm going to do is I'm going to check the tire size.

It's going to say like P22570R15.

And I won't go into what all those numbers mean.

I probably need to though.

But that just is the tire size.

I'm going to open the door and we'll check that little label inside the door jam and make sure that it says that as well.

Because if not, somebody has changed the tire size on the vehicle and that can affect a lot of different things, including my speedometer.

I won't know how fast I'm going because they've changed the diameter, the circumference of the tire, the diameter and the circumference.

And so I'm going to have taken issue with that.

I'm going to say, well, I might be interested in buying the car, but it's got the wrong size tires on it and I want that fixed.

They might fuss and fume, but that's something that's, you know, it's important.

So the air pressure is important too.

So the air pressure stamped on the side of the tire is the maximum air pressure cold when the tires are cold.

You don't want to go any higher than that.

But the engineers who designed the car, they designed it for a certain size tire and they designed that tire to have this much air in it.

You know, it might be 35 pounds.

I jumped into a, what was that?

Oh, it was a frontier pickup truck brand new and sitting out there on the patio.

I just want to see what it drove like because it's got this Roush package on it.

That's some guy that is very famous and he fixes up vehicles, makes them run faster and handle better and so forth.

But anyway, we have a Roush edition Nissan Frontier.

I wanted to see if it really drove any different and it really did.

It rode like a log wagon.

And the reason is I check the air pressure in the tires because, you know, it has an automatic tire pressure sensors.

And I just went to that screen and you know what?

My mechanic failed when he PDI'd that vehicle.

He put, well, he never adjusted the tire pressure because they come with too much tire pressure.

The factory puts it way up there for some reason.

It had 45 pounds in each of the tires.

You know, it's supposed to have 32 pounds.

Thus the bad ride.

And so we reduced the pressures.

I took it on another ride, a totally different vehicle.

I was very impressed.

So my judgment has been corrected.

Did have to talk to the service advisor and he went and talked to the technician.

He said, make sure you check the pressures on these.

Lenny doesn't like it when we don't have the tire pressure set correctly.

And customer takes delivery of the vehicle or takes it on a test drive and they say, man, this thing rides like a log wagon.

And we don't want them saying that.

So go by the sticker in the door jam.

Not what it says on the tire.

So that's about it.

Call me if you need me or send me a text 423-552-2020.

If you got any teens and you live close, relatively close, get them enrolled in our special program we're going to have because we're going to feed them.

It's going to be fun.

They're going to learn stuff.

They won't be sitting there bored.

You know, saying, why are my parents making me come to this?

No, they'll be thanking you after it's all over because they're going to learn a lot about cars that they didn't know.

Things that they need to know and ways to keep them safer once they get out there on the road.

I hope they listen.

I pray that they do.

Well, thanks for listening and I'll see you next time.

How to safely jump-start your dead car battery PLUS, is it the alternator or battery's fault?

About this episode

Mazda

Chevrolet

manual transmission

Chevrolet LUV truck

Isuzu

Ford Mustang

Ford Maverick

lock up torque converters

paddle shifters

dual clutch automatic

jump start

jumper cables

owner's manual

wrecker

positive terminal

negative terminal

battery acid fumes ignition risk

battery cables

rev the engine

parasitic drains

keyless remote

belt tensioner

charging system

loose belt

spark plugs

fuel pumps

fuel injector systems

tire size

Nissan Frontier

automatic tire pressure sensors

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