How to Diagnose and Replace a Starter


Hey guys! ChrisFix here! Today, I’m going to show you how to diagnose
and replace a starter …in your car or truck. In most situations, when the starter goes bad, …it’s completely random and there’s no warning. For example, I got in my truck… I went to go start her up, turn the key… ( starter motor clicking ) …and she won’t start at all!
I just hear a click. So I have a feeling it’s a bad starter… …but it can be a couple of other things. So let me show you how to diagnose
and make sure it IS a bad starter… …and then I’m gonna show you
how to replace the starter. So let’s begin. Now there are four common problems,
other than your starter… …which could prevent your engine from turning over. You could have a dead battery, your anti-theft immobilizer might not be working, your neutral safety switch might be bad, …or… you simply have a blown fuse. So the first thing we want to check,
and probably the most common reason
a car won’t crank… …is the battery. And you can check a battery really easily on your own
with one of these multimeters. Just set it to 20 DC volts, grab the two leads,
touch one to one post and one to the other… …and you can see our voltage is almost 12.4. You want your voltage to be at least 12.2 or above. If it’s lower than that, try charging your battery… …and seeing if the car will start. Now testing voltage helps… …but it doesn’t tell you the whole story, …because it doesn’t put a load on your battery. So you could get yourself a load tester like this, …which will test the cold cranking amps of the battery
under a load. Cranking amps are the amps the battery could deliver
to run the starter. In this case we want to look at cold cranking amps,
which is 850. So we just put it to 850, hit enter, …and now it tests the battery… …and compared to the rated 850,
we have 831 cold cranking amps, …which is pretty close, so that’s a good value. If this was significantly less,
if this was like 600 or even 500, …I’d consider getting a new battery. That could be why your starter isn’t working. Now this load tester is a great tool to have… …and I’ll be sure to link this in the description, along with any products and tools
I use in this video… …so you could easily find them. And if you don’t want to go buy
one of these load testers, …most your local part stores
will load test your battery for free, …so just go ask. Now our battery is good, so the next thing to check …is each terminal. First, you want to make sure that the terminal
is securely connected to the post. A tight connection here is important. Next, check the connection for any corrosion. Even if the corrosion doesn’t seem bad, try disconnecting the terminal,
sanding down the post with, like,
200-grit sandpaper… …and don’t forget the inside of the terminal as well. The slightest bit of corrosion could cause
a bad connection… …and that could prevent the starter from working. So make sure you keep those terminals clean. Now there’s one more thing I want to show you …and that’s inside another car. If you go to start your car… – ( rapid clicking )
– …and you hear a rapid clicking sound, …usually, that’s a dead BATTERY… …and NOT a bad STARTER. You can see the voltage is low,
so just charge it up …and then the car should start. ( charger beeps ) So you always want to check your battery first. It’s one of the most common reasons why your car
or truck won’t start. Another common reason… …is the anti-theft immobilizer. Many cars today have chips in the key, which will prevent somebody from hot-wiring your car. Now if this immobilizer goes bad… you go to start your car… …and it won’t start. Now how do you tell if the immobilizer is bad? Well, you just go to the dash, …put the key in the run position… …and look for the anti-theft light. After a few seconds, it should go out,
if it’s working correctly. So, since the anti-theft light went out,
I know the chip in this key works …and the immobilizer is working properly. But to give you an example of a bad immobilizer, …or bad chip in a key, …I made a blank of my key. If the immobilizer isn’t working, …it’ll stay lit or flash rapidly. So that’s how you tell if your immobilizer’s not working, …which could be a reason
why your car’s not turning over. And since we’re looking at the dash lights,
I have one more thing I want to show you. It’s not very common,
but it’s still worth to check: Put the key in the ignition,
turn it to the run position, …and you want to make sure
that your “Check Engine” light comes on. If your “Check Engine” light doesn’t come on, That could mean the car’s computer isn’t working. And if the car’s computer isn’t working, …the engine might not turn over. So, again, that’s not as common of an issue, …but it’s something to look at,
since we’re already looking at the dash lights. But the next problem’s a common reason
why your engine might not turn over …and that has to do with your neutral safety switch. Now, I’ve done this before myself. Sometimes, on an automatic car,
when you go to put the car in park, …you end up not pushing it all the way into “Park,” …so it’s in between reverse and park. And as a safety feature, …the neutral safety switch will prevent your car
from starting… …if it’s not in neutral or park. On automatic cars, the neutral safety switch
is connected to the transmission. So just go underneath the vehicle. You can see the transmission pan is right here, …and then right next to the transmission pan
is the neutral safety switch. So when you shift into gear,
the neutral safety switch lets your car know
what gear you’re in. Now, a bad neutral safety switch will usually throw
a “Check Engine” light. But one thing that check
is to make sure your electrical connection
is pushed all the way in, …because they can loosen from all the vibration. Now, that’s for automatic cars. Manual cars are a little bit different. For a manual, even if you’re in neutral,
the car… won’t start. You have to press the clutch down,
and that… – ( engine starts )
– …allows you to start the car. When you press the clutch,
the clutch safety switch, which is connected
to the clutch, is engaged, …which allows the car to start. So make sure that the clutch safety switch looks good… …and is plugged all the way in. So that’s something you’ll want to check
on a manual car. And the last thing to check
before replacing your starter… …are the fuses and relays. And if you aren’t sure where your fuse box is
for your starter, …you could check your owner’s manual. In here, you’re gonna get a diagram, …and… it’s gonna tell you exactly where the fuse is
for the starter relay, …and it’s also going to show you
where the starter relay is. And we’re gonna check both. Now first, we’re gonna check that starter
relay fuse, which is right here, …and make sure it’s not blown. And this is like checking any other fuse.
Just make sure the connection’s not broken
in the fuse… …and this one looks good. Although these fuses are a little bit different,
if we put 35 amps across these, ( fuses pop ) …they pop and that’s what a bad fuse looks like. So we know our fuse is good. Now we’re gonna go check the starter relay,
which is this one right back here. To test this, have somebody start the car… …and with your finger on the relay,
you should feel… …and also hear a click. ( relay clicking ) This clicking usually means the relay is working, …but to be sure, you could remove the relay
and swap it out with another one. – Now with both relays in,
we could try starting the truck.
– ( starter motor clicking ) Again, I could hear the click,
but the starter isn’t engaging. So we know the relay is good. Now, after checking the fuse and the relay
and determining that they’re good, …we’ve checked many of the common problems… …that would cause a vehicle not to turn over. So I’m pretty confident that it’s the starter that’s bad. And with that being said, there’s one more thing,
it’s kind of old-school that I want to show you, …and it’s hitting the starter with a hammer
to try to get the car started. So have somebody trying to start the vehicle
as you’re underneath… …trying to hit the starter with a hammer. Ready? ( hammer bangs on starter,
bell chiming ) ( banging continues ) ( engine starts ) ( engine idling ) So, there you go! It’s a good little trick
that’ll get you home… …and now we also know that starter is definitely bad. – OK, cut it!
– ( engine turns off ) Now many starters are accessed
from underneath the vehicle. I already showed you because I was hitting it
with a hammer. My starter is underneath the engine. And some cars, like this Jaguar, …the starter is located at the top. You can see the starter solenoid,
and right below, that’s the starter. So you could actually get access
to the starter from the top of the motor;
you don’t have to go underneath. So you’re going to want to figure out
where your starter is located. And in this case, I need the safety jack up my truck. And be sure to rest the weight of the vehicle
on the jack stands, just like that. And then I like to leave the jack
slightly touching the frame
for some extra protection. And with the vehicles safely supported on jack stands, I like to come over and give it a good shake;
make sure it’s nice and solid, …and it is. So now let’s go remove the starter. Replacing the starter on most vehicles
is fairly simple. All you need are some common hand tools.
I always start off with some safety glasses
because we’re working underneath the vehicle, …need a good socket set with some extensions, …a couple of wrenches and then some threadlocker… …for when we install the new starter. So let’s begin. And before we start removing the starter,
the first thing you want to do… …is disconnect the battery
by removing the negative lead… …so that there’s no power going to the starter. Now under the truck,
we’re moving towards the front of the truck,
passing the transmission pan, …the cat, and ending up at the oil pan. To find your starter,
you’re gonna want to find where the engine
and transmission meet, …because that’s where the flywheel is, …and the starter engages the flywheel
to spin the engine. So if we look closer, the starter is right here. I’m gonna loop around to the other side
for a better view of how its bolted in. So the starter is right here and there’s a bolt here, …a bolt here and a bolt back there. And that’s all that holds in the starter. Now, since there isn’t too much room
to remove these bolts, I’m gonna be using a ratchet with a swivel head. So let’s get all three bolts removed. And they give you… just enough room
to get the ratchet and your fingers in there
to get the bolt out. Let’s get the bottom bolt next,
which has more room than the last bolt. And that’s the second bolt… …and now we have one more bolt
all the way up at the top. And it’s gonna be tough to get to that one, …but there’s a trick. And that trick is to use a universal joint
with an extension. The U-joint extension can be pretty loose, …so a little trick is to use some black tape
to limit its motion. And we’ll snake that socket back there and loosen the bolt. Since this is the last bolt holding the starter in,
as you remove it, …make sure you hold the starter so it doesn’t just drop,
because it’s pretty heavy. ( starter clattering ) There we go. Now I’m gonna rotate the starter
so we can get access to the wires. Before we remove the wires,
just note where the wires go. In this case, there are two different size wires;
one here… …and one there. And the other thing I want to mention, …sometimes the starter isn’t actually bad;
rather the connection is bad, …because it’s all corroded. So you could always try taking the wires off,
cleaning the connection, and putting them back on, …and the starter might work. But the connection here looks good,
so let’s remove the wires. We have the smaller nut first,
which is a 10 mm. Good. Get that wire off there. And then we had the larger nut,
which is a 12 mm… …and get that wire off. Good. This is a tight fit,
but with a little bit of wiggling… ( starter clattering ) …the starter is out. Now this is out, let’s go to the parts store… …and get the new starter. Be sure to bring your starter with you, …and I’m gonna show you why. I’m at my local AutoZone,
and they could actually test the starter… …to see if it’s bad. What they do is they hook up the starter
to their tester, …connect some wires, …and then test it out. ( machine whirring ) And just as I figured, the starter is bad. And besides bringing your starter in
to get tested for free, …it’s important to bring it,
because when you get your new starter, …you can hand over your old starter
so you don’t get to charged court And thank you, AutoZone, for supporting the video… …and letting me film in the store. Alright, so now back under the truck, …we can install our new starter! But before we go put this back in, …we want to clean the wires
that are gonna attach to this so we have
a good electrical connection. Use some sandpaper and just sand away
any of the corrosion. And this looks good, …so let’s do the other wire as well. Sand that clean. Now, with both wires prepped, …let’s squeeze our starter back into place. ( starter clattering ) Good. Now installation is simply the opposite of removal. First, connect the two wires. Now, the other wires shorter,
so we have to move the starter… …to get the wire over the post… Then tighten it down. Next is an awesome trick that prevents corrosion… …and keeps the starter running great, …and that’s using silicone paste on the wires
we just tightened down. Silicone’s an electrical insulator, …and it’s hydrophobic, so it prevents water
from contacting the posts and wires… …on the starter, so they’ll stay corrosion-free. So give the exposed metal wires
a light coat of silicone… …and now we could bolt in the starter,
so let’s spin it around, …push it in, …and line up the bolt holes. So with the starter lined up, …grab your three bolts, …and we want to use some
removable threadlocker on these. Threadlocker not only prevents the bolts
from loosening due to vibrations, …but also coats the threads,
which will help prevent corrosion. So just use a little bit on the ends of the threads, …then start with the easiest bolt to get to — So, the bottom one —
…and start threading the bolt into the starter. Once you have the thread started by hand, …tighten the bolt down most of the way,
but leave it loose enough… …so that you can align the other two bolts. Now, tighten the next easiest bolt,
which is the middle one, …and you can see how we’re putting
a swivel ratchet to good use
in these tight spaces. And finally, we have our universal joint
and extension for the last
and hardest-to-reach bolt. Get it in place and tighten it down completely… …to 20 ft-lbs. Now we’re gonna torque down the other two bolts. That’s one… …and that’s the other. Now all three bolts are torqued, …the wires are connected, …and the starter is completely in. And like I said, the job is relatively easy. It all depends on where your starter is. The hardest part with this: We’re just having enough room in this area. Which is why having the right tools
makes the job go THAT much easier. Now, it did get dark out, …so I’m gonna kill the lights,
and we’re gonna start her up in the morning. ( garage door motor whirring ) And it’s a good thing we got that done yesterday, …because it snowed. So let’s go pop the hood
and get that negative terminal on there. Make sure that’s nice and tight. ( hood slams shut ) And with the battery connected, …let’s go start up the truck. I don’t know about you guys, …but this is always my favorite part
whenever you fix something, …going to start her up, see if she works. Moment of truth. ( engine cranks, then starts ) All right! Now, that’s what I’m talking about! That starter sounded nice and strong, …and she started right up with no strange noises. And that’s how you replace a starter. As always, hopefully the video was helpful, …and if it was, remember to give it a thumbs up. I want to hear your starter-changing stories… …from the easy ones to the tough ones. So make sure you leave a comment below. Plus, if you aren’t subscribed, consider subscribing. And finally, all tools and products I use in this video
are listed in the description