How To Test The Starter Motor (1996-1999 5.0L, 5.7L V8 Engines)

When the stater motor fails, it'll usually just not crank the engine. You'll turn the key to crank and start the engine, but nothing happens.

The cool thing is that testing the starter motor isn't that hard. This tutorial will help you test the starter motor on the 1996, 1997, 1998, and 1999 Chevrolet and GMC equipped pickups with a 5.0L and 5.7L V8 engine.

All the test steps are explained in a step-by-step way.

You'll be able to find out if the starter motor is defective or not.

Important Safety Tips And Precautions

TIP 1: Don't remove the starter motor to test it, since the starter motor test (in this tutorial) is an on-car test.

If you have removed it, you can bench-test it and the following tutorial will help you: How To Bench Test A Starter Motor (Step By Step).

TIP 2: It's very important that the battery be fully charged before doing the tests.

Also, the battery posts and battery terminal cables should be clean and corrosion free.

TIP 3: If your vehicle has a standard transmission, make sure that it's out of gear and in neutral, and that the parking brake is activated/on.

Tools Needed To Test The Starter Motor

Here's a list of the tools I recommend you use to follow the test steps in this tutorial:

1. Remote starter switch.
   • If you'd like to see what a remote starter switch looks like, you can follow this link: Innova 3630 Remote Starter Switch (Amazon affiliate link)
   • You can either buy this tool online or you can buy it at your local auto parts store (AutoZone or O'Reilly Auto Parts, etc.).
2. Multimeter or a 12 Volt automotive test light.
   • If you don't have a multimeter or need to upgrade yours, check out my recommendation here: Tekpower TP8268 AC/DC Auto/Manual Range Digital Multimeter (Amazon affiliate link).
3. A wire piercing probe.
   • This tool is not an 'absolute must-have tool' but I can tell you from experience that it makes it a whole lot easier to probe the S terminal wire for the start signal.
   • If you'd like to see what this tool looks like, you find out more about it here: Wire Piercing Probe Tool Review (Power Probe PWPPPPP01).
4. A helper.

As you can see these tools are anything but expensive and more importantly, they'll help you test it without complications.

TEST 1: Applying 12 Volts To The Starter Motor S Terminal

The first order of business is to apply 12 Volts to the starter solenoid's S terminal with a remote start switch.

The remote start switch will act as our ignition key and is the safest way to manually apply battery power to the starter motor solenoid's S terminal.

If the starter motor is functioning correctly, then manually applying 12 Volts (from your pickup's battery) to it should get it to engage and crank the engine.

If the starter motor is defective, then juicing it up manually with 12 Volts will have no effect on it.

IMPORTANT: Before you perform this test remove the key from the ignition switch to prevent the engine from accidentally starting.

IMPORTANT: Use jack stands when raising your vehicle to access the starter motor. Don't trust the jack to keep your pickup or SUV up in the air!

OK, these are the test steps:

1. 1

   Disconnect the battery negative (-) terminal.
   
   You'll reconnect it back in one of the following steps, for now, it's a safety precaution as you set up the test.

2. 2

   Attach one of the alligator-type terminals of the remote starter switch to the S terminal of the starter motor.

3. 3

   Reconnect the battery negative (-) cable to the battery negative (-) post.
   
   NOTE: Make sure that the battery cables and posts are clean.

4. 4

   Connect the remaining alligator-type terminal of the remote starter switch to the battery positive (+) post.
   
   IMPORTANT: If your Chevy/GMC pickup or SUV has a standard transmission, make sure it's out of gear before you make this last connection.

5. 5

   Activate the starter motor with your remote starter switch. As you apply these 12 Volts (to the S terminal of the starter motor), you'll get one of two results:
   
   1) The starter will activate and will turn over the engine -OR- 2) The starter motor won't do a thing.

Let's examine your test result:

CASE 1: The starter motor cranked the engine. This is the correct test result and tells you that the starter motor itself is OK.

Since the starter motor is not engaging when you use the ignition key, the next step is to go to: TEST 2: Verifying The Start Signal.

CASE 2: The starter motor DID NOT crank the engine. This usually means that the starter motor is bad and needs to be rebuilt or replaced.

I suggest 2 more tests and these are make sure that the starter motor is getting its 12 Volt signal and to test the battery cable (that attaches to the starter motor solenoid) for corrosion. This can be accomplished very easily with a voltage drop test.

• Go to: TEST 2: Verifying The Start Signal.
• Go to: TEST 3: Voltage Drop Testing The Battery (+) Cable.

If the above two tests confirm that the start signal IS present and there's no voltage drop on the battery cable (feeding battery power to the starter motor), then you can confidently conclude that the starter motor is bad and needs to be replaced.

TEST 2: Verifying The Start Signal

Since the starter motor is not engaging the engine, when you turn the key to crank and try to start it, we now need to verify the presence of the Start signal.

The Start signal is the voltage signal that activates the starter motor and is received on the starter motor solenoid's S terminal.

This test simply involves connecting our multimeter to the S terminal wire and turning the key to crank and start the engine.

If the Start signal is present, then your multimeter should read 10 to 12 Volts DC. If it isn't, then it'll just read 0 Volts DC.

Let's get going:

1. 1

   Connect the red multimeter test lead to the S terminal of the starter motor.

2. 2

   Attach the black multimeter test lead to a clean and rust-free spot on the engine or on the vehicle frame.
   
   I recommend that you use a battery jump start cable to Ground the black multimeter test lead directly to the battery negative (-) terminal.

3. 3

   Have your helper crank the engine from inside your Chevy/GMC pickup or SUV.
   
   The engine won't turn over, but the idea is to verify that the starter motor's internal solenoid is getting the 12 Volt start signal from the ignition switch (or not).

4. 4

   Your multimeter is going to register one of two results: Either 10 - 12 Volts DC or no voltage at all.

Let's examine your test result:

CASE 1: The multimeter registered 10 to 12 Volts. This test result lets you know the starter's internal solenoid is receiving the start signal.

This means that we can forget about the safety neutral switch and the ignition switch being bad. OK, now the next test is to do a very easy and simple voltage drop test. Go to: TEST 3: Voltage Drop Testing The Battery (+) Cable.

CASE 2: Your multimeter DID NOT register 10 to 12 Volts. This result exonerates the starter motor. Your starter motor is not the cause of the no-crank condition.

Here's the reason why: Without this 10 to 12 Volt crank signal, the starter motor will not engage and crank your pickup or SUV's engine. Now, although it's beyond the scope of this article to test the neutral safety switch or the ignition switch, you have eliminated the starter motor and this means saving money by not buying a part your vehicle does not need.

TEST 3: Voltage Drop Testing The Battery (+) Cable

In some cases the starter motor won't crank the engine even though the battery is fully charged, the engine isn't locked up (like when it throws a rod), the starter solenoid is receiving the Start signal, and the starter motor bench-tested good.

In these cases what is usually causing the problem is hidden corrosion in the battery cable that connects the starter to the battery.

The best way to confirm this is to do a voltage drop test. Yup, this test will help us to make sure that all of the battery's current is reaching the starter motor.

This is a very easy test to do and all you need is a multimeter. These are the test steps:

1. 1

   Place your multimeter in Volts DC mode.

2. 2

   Attach the red multimeter test lead to the center of the positive battery terminal.
   
   If the positive battery post isn't clean, clean a spot right on the top of it. It's important that the multimeter lead make contact right in the center of the positive battery post.

3. 3

   With the black multimeter test lead, touch the center of the starter stud to which the big battery cable attaches to. You'll maintain the black multimeter test lead in this position throughout the next step.

4. 4

   Have your helper crank the engine even though the starter motor isn't cranking the engine.
   
   This is important, since a voltage drop test has to be done while the component in question is working (or trying to work).

5. 5

   If all is good (no voltage drop), your multimeter will register 0 Volts (.5 Volts is still 0 Volts).
   
   If there's a voltage drop (which is bad), your multimeter will register voltage (usually above 5 Volts DC).

Let's take a look at what your results mean:

CASE 1: Your multimeter registered 0 Volts (no voltage drop). This result indicates that the starter motor is receiving all of the battery voltage and amperage it needs to crank the vehicle.

You can conclude the starter motor, on your Chevy/GMC pickup or SUV, is defective if you have:

1. Confirmed that the starter motor doesn't work when you apply power to the S terminal wire of the starter motor (TEST 1).
2. Confirmed that the starter motor is receiving the crank signal (TEST 2).
3. In this test step, you have confirmed that no voltage drop exists on the battery positive cable.

Replacing the starter motor should solve your no-crank condition.

I'm going to make two more recommendations to you:

• Before removing the starter motor, manually turn the engine using a 1/2 ratchet and the appropriate socket. This is to make sure that the engine or the A/C compressor have not locked up and causing the no-crank condition.
• Bench test the starter motor after removing it. This is a super easy test to do and this tutorial will help: How To Bench Test A Starter Motor (Step By Step).

CASE 2: Your multimeter registered 5 Volts or more. This result tells you that a voltage drop does exist and that the battery's full power is not reaching the starter motor.

The good news is that this can easily be corrected, since a voltage drop is always caused by some sort of corrosion issue on the battery positive cable or terminals or the battery positive (+) post.

The solution is to thoroughly clean the battery positive (+) post and the battery positive (+) terminal (both the end that attaches to the battery positive (+) post and the end the connects to the starter motor's battery (+) cable stud.

After cleaning, try cranking the engine. If it cranks and starts, no further testing is required.

Where To Buy The Starter Motor And Save

You can buy the OE starter motor (AC Delco) online far cheaper than the brand-X starter motor at your local auto parts store. The following links will help you comparison shop for the starter motor on your 1996-1998 V8 equipped Chevy/GMC pickup or SUV:

More GM 4.3L, 5.0L, And 5.7L Tutorials

You can find a complete list of GM 4.3L, 5.0L, and 5.7L tutorials in this index:

• GM 4.3L, 5.0L, 5.7L Index Of Articles.

Here's a small sample of the tutorials you'll find in the index:

• How To Test A Misfire / No Spark-No Start Condition (4.3L, 5.0L, 5.7L 96-04).
• How To Clean The GM Mass Air Flow (MAF) Sensor.
• How To Test The Throttle Position Sensor (GM 4.3L, 5.0L, 5.7L).
• How To Test The GM Ignition Control Module (1995-2005).