How To Test The Starter Motor (3.4L V6 Chevrolet, Pontiac)

Testing the starter motor isn't difficult and can be done without expensive diagnostic tools. In this tutorial, I'll explain how to do it step-by-step.

With your test results, you'll easily find out if the starter motor is good or bad.

NOTE: The starter motor test in this tutorial is an on-car test. The photos I'm using show the starter motor off of the vehicle only to explain the test connections better.

You can find this tutorial in Spanish here: Cómo Probar El Motor De Arranque (1996-2005 3.4L Chevrolet, Pontiac) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.4L V6 Chevrolet Impala: 2000, 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Chevrolet Lumina Minivan: 1996.
• 3.4L V6 Chevrolet Monte Carlo: 2000, 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Chevrolet Venture: 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Pontiac Aztek: 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Pontiac Grand Am: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Pontiac Montana: 1999, 2000, 2001, 2002, 2003, 2004, 2005.
• 3.4L V6 Pontiac Trans Sport: 1996, 1997, 1998.

STARTER MOTOR BENCH TEST:

• How To Bench Test A Starter Motor (Step By Step).

Important Testing Tips

TIP 1: The battery must have a full charge before starting any of the tests in this tutorial.

TIP 2: The battery cable terminals and the battery posts should be clean and corrosion-free before starting the tests.

TIP 3: Read the entire article first to familiarize yourself with the tests.

TIP 4: Use jack stands for safety. Don't trust the jack alone to keep your vehicle up in the air while you're underneath it!

TIP 5: Take all necessary safety precautions. Use safety glasses while working underneath the vehicle. Be alert and think safety all of the time.

Symptoms Of A Bad Starter Motor

Generally, when the starter motor fails in your 3.4L V6 Chevrolet or Buick, the engine will not crank. To be more specific, when you turn the key to crank and start the engine, nothing happens.

Unfortunately, this isn't the only way the starter motor fails. In some cases, it'll fail intermittently.

In plain English, the starter motor will function most of the time when this happens, but now and then, it won't.

The key to troubleshooting an intermittent no-crank issue is to perform all tests when the starter motor is not functioning. Otherwise, your test results will indicate the starter motor is good.

Tools Needed To Test The Starter Motor

To test the starter motor on your vehicle, you don't need any expensive tools or diagnostic equipment. Yep, the tools you'll need are not gonna break the bank.

Here's a list of the things we'll need to test the starter motor on your vehicle:

• Jack.
  • You'll need to raise your vehicle to gain access to the starter motor.
• Jack stands.
• A 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.).
• A 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).
• 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).
• A helper.

TEST 1: Applying 12 Volts To The 'S' terminal

The first thing that we'll do is apply 12 Volts directly to the starter motor solenoid's 'S' terminal.

The easiest and safest way to apply these 12 Volts to the starter motor is to use a remote starter switch.

If you don't have a remote starter switch, you can buy one at your local auto-parts store or online. See my recommendation here: Innova 3630 Remote Starter Switch (Amazon affiliate link).

If the starter motor activates and cranks the engine (when applying 12 Volts to its 'S' terminal), then you can conclude right off the bat that the starter motor itself is OK.

IMPORTANT: Remove the key from the ignition switch for this test.

OK, let's get started:

1. 1

   Raise the front of your vehicle and place on it jack stands (to gain access to the starter motor).

2. 2

   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.

3. 3

   Attach one end of the remote starter switch to the battery positive (+) post.

4. 4

   Attach the other end of the remote starter switch to the 'S' terminal of the starter motor solenoid.
   
   This is easier said than done, so take your time and make sure the connection is on the 'S' terminal of the starter motor solenoid.
   
   In case you're wondering, you can leave connected the wire that connects to the 'S' terminal stud on the starter solenoid. Whether or not that wire is connected to the S terminal, the test works either way.

5. 5

   Reconnect the battery negative (-) cable to the battery negative (-) post.

6. 6

   Apply 12 Volts to the 'S' terminal wire of the starter motor starter solenoid with your remote starter switch.

7. 7

   You'll get one of two results:
   
   1.) The starter will activate and will turn over the engine.
   
   2.) The starter motor won't do a thing.

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

CASE 1: The starter motor cranked the engine. This is the correct and expected test result and it confirms that the starter motor is good.

Since the starter motor is not cranking the engine when you use the ignition key, the next step is to see if it gets an activation signal. For this test go to: TEST 2: Verifying The 12 Volt Start Signal.

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

I suggest you perform two more tests. First, make sure the starter motor is getting its 12 Volt Start signal. Second, voltage drop test the battery cable (that attaches to the starter motor solenoid).

• Go to: TEST 2: Verifying The 12 Volt Start Signal.
• Go to: TEST 3: Voltage Drop Testing The Battery (+) Cable.

TEST 2: Verifying The 12 Volt Start Signal

There's a good chance the starter motor is not receiving an activation signal if:

• The starter motor activates only when you apply 12 Volts to its 'S' terminal.
• The starter motor DOES NOT activate when you turn the ignition key to crank and start the engine.

In this test section, you'll check the wire that connects to the 'S' terminal (on the starter motor solenoid) and see if it delivers an activation signal.

NOTE: You can perform this test with the 'S' wire connected or disconnected to the 'S' terminal.

These are the test steps:

1. 1

   Raise and place the front of the vehicle on jack stands (if it isn't already).

2. 2

   Place your multimeter in Volts DC mode.

3. 3

   Ground the black multimeter test lead directly on the negative (-) battery terminal using a jump start cable.
   
   You can also Ground it on the engine, if you can find a clean, unpainted and rust-free spot of metal.

4. 4

   Connect the red multimeter test lead to the 'S' terminal wire using an appropriate tool.
   
   Don't know which wire is the 'S' terminal wire? This is the one that connects to the smaller of the three studs on the starter motor solenoid.
   
   The 'S' terminal wire (circuit) is the one that delivers the Start (Crank) signal from the ignition switch.

5. 5

   Have your helper turn the key to crank the engine when the test is setup.

6. 6

   Your multimeter should read 10 to 12 Volts DC.

OK, let's interpret your test results:

CASE 1: Your multimeter registered 10 to 12 Volts. This is the correct and expected test result and it confirms that the starter motor is receiving its activation signal.

Now, in most cases, you could stop here and replace the starter motor and be done. But, I suggest one more test so that you can be absolutely sure there isn't another issue to deal with.

Your next test is to voltage drop test the battery positive (+) cable. This is a very easy and simple test to do. Go to: TEST 3: Voltage Drop Testing The Battery (+) Cable.

CASE 2: Your multimeter DID NOT register 10 to 12 Volts. This test result lets you know that the starter motor isn't receiving an activation signal.

Although finding out why this activation signal is missing is beyond the scope of this tutorial, the most likely causes are:

• A bad starter motor relay.
• A bad park-neutral safety switch.
• A bad clutch pedal switch.
• A bad ignition switch.
• An anti-theft system fault.

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

So far, your test results have confirmed:

• The starter motor does not activate when applying 12 Volts to its 'S' terminal (TEST 1).
• The starter motor solenoid's 'S' terminal is receiving an activation signal (TEST 2).

In this last test section, we're going to make sure that the wire that connects the starter motor to the battery doesn't have corrosion or a false contact issue.

Why? Because the starter motor will receive a lower amperage due to these two problems. This lower amperage could cause the starter motor not to crank the engine.

We'll check for these two issues by doing a multimeter of voltage drop test on the starter motor's battery wire.

The voltage drop test is a super simple test that will let you know if the starter motor is receiving all of the battery's amperage output.

Let's start:

1. 1

   Place your multimeter in Volts DC mode.

2. 2

   Attach the red multimeter test lead to the positive (+) battery post. The positive (+) battery post must be clean and corrosion-free.
   
   You may need two helpers for this test step, since someone will have to hold the red multimeter test lead onto the battery positive (+) terminal bolt and someone else inside the vehicle (to crank it when everything is set up).

3. 3

   Place the black multimeter test lead on the starter motor solenoid stud that connects to the battery positive (+) cable (see illustration above).
   
   The orange arrow with the plus (+) sign, in the illustration above, points to this stud.
   
   Maintain the black multimeter test lead in this position throughout the next step.

4. 4

   When everything is ready, have your helper turn the key to crank the engine.
   
   Although the starter motor won't crank the engine, your helper has to turn the ignition switch to start the engine for the voltage drop test to work.

5. 5

   The multimeter should register 0.5 Volts or less (0.5 V = 0 Volts).
   
   If there's a problem in the wire, your multimeter will register some voltage, usually 5 Volts or more.

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

CASE 1: Your multimeter indicated NO voltage drop (which is 0.5 Volts or less). This is the correct test result and it confirms the starter motor is receiving all of the battery voltage and amperage it needs to crank the engine.

You can conclude that the starter motor is bad and needs replacement if you have:

• Confirmed that the starter motor only cranks the engine by applying 12 Volts directly to the 'S' terminal of the solenoid (TEST 1).
• Confirmed that the starter motor is receiving an activation signal (TEST 2).
• Confirmed, in this test section, that the battery positive (+) cable does not have a voltage drop issue.

Now, before you remove the starter motor, do one more important thing:

• Turn the engine manually (using a 1/2 ratchet and the appropriate socket on the crankshaft pulley bolt). This will check to see if the engine is mechanically locked up (or not).

If you'd like to bench test the starter motor (after removing it). You can find the step-by-step instructions here:

• How To Bench Test A Starter Motor (Step By Step).

CASE 2: Your multimeter registered 5 Volts or more. This result confirms that the starter motor is not receiving the battery's total amperage output.

This voltage drop is almost always caused by corrosion or a false-contact issue with the battery wire.

To solve this problem, you'll need to thoroughly clean both ends of the battery positive (+) cable.

Cleaning the end that attaches to the starter motor solenoid should be done with a small piece of sandpaper. Once both ends of the battery positive cable are clean, reconnect everything and try cranking the engine.

If the voltage drop was the cause of the no-crank condition, the starter motor will now crank the engine.

More 3.4L V6 Chevrolet, Pontiac Tutorials

You can find a complete list of 3.4L V6 Chevrolet (Pontiac) tutorials in this index:

• GM 3.4L Index Of Articles.

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

• How To Test Engine Compression Test (3.4L V6 Chevrolet, Pontiac).
• How To Test A Blown Head Gasket (3.4L V6 Chevrolet, Pontiac).
• What Does The CKP Sensor Do? (3.4L V6 Chevrolet, Pontiac).
• How To Test The Throttle Position Sensor (3.4L V6 Chevrolet, Pontiac).