How To Test The Starter Motor (1992-1993 3.3L V6 Pontiac Grand Am)

Testing the starter motor on your 3.3L V6 Pontiac Grand Am can seem like quite a challenge, but nothing could be further from the truth.

In this tutorial, I'll explain how to test the starter motor step-by-step. You'll easily and quickly 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 (1992-1993 3.3L V6 Pontiac Grand Am) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.3L V6 Pontiac Grand Am: 1992, 1993.

STARTER MOTOR CIRCUIT WIRING DIAGRAM:

• Starter Motor Circuit Diagram (1992-1993 3.3L Pontiac Grand Am).

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, it will not crank the engine. To be more specific, nothing happens when you turn the ignition key to crank and start the engine.

In some cases, the starter motor fails intermittently. When this happens, the starter motor works fine most of the time, but now and then, it doesn't. Unfortunately, these intermittent problems are the hardest to diagnose.

The key to successfully troubleshooting an intermittent no-crank problem is to test the starter motor when it's not cranking the engine.

Tools Needed To Test The Starter Motor

The starter motor is probably one of the easiest components to test on your 3.3L V6 Pontiac Grand Am since you don't need any expensive diagnostic equipment to do it.

Here's a list of the essential tools you need to test a starter motor:

• 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 DC directly to the starter motor solenoid's 'S' terminal.

This is an easy test, but only if you use a remote starter switch. Don't worry. It's not an inexpensive tool, and you can buy it at your local auto parts store or online.

If you don't have one and need to buy one, you can buy it here: Innova 3630 Remote Starter Switch (Amazon affiliate link).

If the starter motor activates (when applying 12 Volts to its 'S' terminal), you can conclude that it's functioning correctly.

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

OK, these are the test steps:

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.
   
   Also, in case you're wondering, you can leave the starter motor solenoid's 'S' terminal wire connected to the engine's wiring harness connector or not, the test will work 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.

You can conclude that the starter motor itself is OK. The next step is to see if the starter motor gets the 12 Volt Start signal on the 'S' terminal wire. 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

The starter motor needs an activation signal to activate and crank the engine.

This activation signal is only delivered when you turn the ignition key to crank and start the engine.

The wire that delivers this activation signal is the one that connects to the starter motor solenoid's 'S' terminal.

You'll do a multimeter voltage test on this wire to check for the presence of this activation signal when your helper turns the ignition key to crank and start the engine.

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

The starter motor needs all of the battery's available amperage to crank the engine.

A common problem is the battery wire (that connects the starter motor to the battery) develops corrosion or a false-contact connection issue in one or both ends.

If the starter motor's battery wire has developed one of these two issues, the starter motor will not receive the battery's total amperage output. This will result in an engine no-crank problem.

So in this test section, you'll do a simple multimeter voltage drop test to check the condition of the wire. The result of your voltage drop test will reveal if the starter is receiving the total output of the battery.

Let's begin:

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 does not crank the engine (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's battery wire has corrosion or a false-contact issue (and it's not a good thing).

The issue causing the voltage drop in the wire will prevent the battery's total amperage output from reaching the starter motor.

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

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 3.3L Pontiac Grand Am Tutorials

You can find a complete list of 3.3L V6 Pontiac Grand Am tutorials in this index:

• GM 3.3L Index Of Articles.

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

• What Does The MAF Sensor Do? (3.3L V6 Pontiac Grand Am).
• How To Test A Blown Head Gasket (3.3L V6 Pontiac Grand Am).
• How To Test The Throttle Position Sensor (3.3L V6 Pontiac Grand Am).
• How To Test The MAF Sensor (3.3L V6 Pontiac Grand Am).