Reasons for Replacing

The first thought that you might have a problem with your starter would be the fact that your car either cranks slow with no loss of other electrical consumers or it becomes noisy when turning the key to start the engine. As starters age they become very tired, just as you will when you get older.

The amount of electricity that passes through a starter in it’s lifetime is amazing. A known good starter draws about 150-200 amps during cranking. When they wear out they begin to increase the amount of amperage by 2 to 3 times(400-600 amps), assuming that the battery can handle it. Think about the number of times you turn the key on your car every day, year, or decade. Chances are, if you’ve owned a car longer than 10 years then you’ve had a starter fail or give you problems at some point during that time. If not, then your on borrowed time.

Starter Testing

If your starter is drawing a large amount of current, refer to the Battery, Starter, and Alternator Testing to learn how to perform a test and read the results for the starter current draw.

Starter Recommendations

From my observation over the years, I truly believe the factory starters that originally come on your car are the best and longest lasting starters ever. Regardless of the manufacture. Yes you can go and get an aftermarket re-manufactured starter for 1/3 the cost of a factory starter, but they do not last as long. Look at it this way, if you really like the car and plan on keeping it for a long time use a factory starter. If it’s a car that you just want to get rid of, save yourself the expense of a factory starter and buy an aftermarket one.

Difficulty Scale

This is an advanced skill level job. It requires access from under the vehicle when removing the starter and it’s mounting bolts.

Tools for the Job

• 1/4″ ratchet
• 5/16″ socket
• 3.8″ drive ratchet
• 10mm socket
• 13mm socket
• 3/8″ extension 12″ long
• 10mm wrench
• 13mm wrench

Prep for Starter Removal

Locate the starter to be removed. Once again the subject being worked on is a 1995 Monte Carlo with a 3.1 liter V6 engine. Even with very little access, the starter is only held on with 2 mounting bolts, 1 trim cover, and 2 nuts for the wiring.

The starter is located toward the front of the vehicle close to the bottom of the engine.

Note: If you don’t have an automotive lift for accessing removal of the starter, refer to the How to use a jack and stands article for helpful knowledge on using a jack and stands to aid in the replacement of the starter.

Considering that we are working with a component that is wired directly to the battery, the first and most important thing to do is to disconnect the battery before servicing the starter.

All side post batteries have a 5/16″ or 8mm socket size to remove the battery cable.

Important Electrical Caution!!!

Always remember, when disconnecting the battery remove the negative terminal/ground cable first!!! This is to prevent any possible contact with surrounding grounds.

If you touch a ground no problems can occur if your removing the ground cable. On the other hand, if you contact a ground while removing the positive of a live battery you can short circuit the battery and do significant damage to the vehicles electrical system.

Removing the Starter

After disconnecting the battery, use the 13mm wrench to loosen and remove the nut holding the battery positive cable to the starter.

Remember that if the battery was not disconnected this would be a live wire and could short to ground if inadvertently touched when replacing.

Use the 5/16″ socket with ratchet to remove the S terminal wire from the starter.

After jacking up and supporting the vehicle, now is when you need to access the starter from underneath the car. Once under the car locate the starter bolt cover.

Using a 10mm socket and ratchet, remove the cover hold down bolt. This will allow access to the main starter mounting bolts.

Remove the front starter bolt with the 13mm socket, extension, and ratchet.

Remove the rear starter mounting bolt.

Be prepared to support the starter when removing the last bolt. Now the starter just need to be removed.

Noisy Starters Take Note:

Whether the starter that you are replacing was making a loud grinding noise or not, it’s always wise to check the teeth on the flywheel for wear.

Before you install the new starter, check the flywheel teeth where the starter mates up to for turning the engine.

Rotate the engine from the front crank bolt while watching the flywheel teeth looking for any shiny or worn spots. Most of the time when the starter makes a grinding noise it’s damaging the flywheel teeth when they mesh.

By carefully looking at all of the teeth you can make sure that no damage is present that could cause damage to the new starter. Worn flywheel teeth can damage and/or shorten the life of the new starter.

The down side to needing a flywheel is that the transmission will need to be removed for access to replacing the flywheel. Yet another post that will soon come.

Re install the new starter in reverse order and re-test using the Battery, Starter, and Alternator Testing post to test the new starter for proper operation.

Estimate for Repair

(check with your local parts stores for current prices)
Parts to replace
Using aftermarket parts you can purchase a remanufactured starter for around $90. New starters around $200.
Labor to replace
This job should cost approximately .5 hr. labor to test the starting system and 1.5 hrs. to replace the starter assembly. (Example: 2hrs.@ $80)
Parts and Labor
Re-man price/ $250
New price/ $360
Note: Factory parts and shop labor rates will be higher depending on type of repair shop and location.
Time to replace
This job should take an experienced technician approximately 1.5 hours to complete

Reasons for Replacement

A majority of the time when an alternator fails, it stops charging and the battery goes dead. Other times the alternator over charges and cooks the battery. For testing and evaluating of the battery, starting, and charging system refer to the Battery, Starter, and Alternator Testing post to help with diagnosis.

Difficulty Scale

This job may not be time consuming, but there are a few steps that are critical when replacing an alternator. This skill level is more for the advanced level technician. Follow along and learn these important steps.

Tools for the Job

• 1/4″ ratchet
• 5/16″ socket
• 3/8″ ratchet
• 13mm socket
• 15mm socket
• 3/8″ extension 6″ long

Prep for Alternator Removal

Always evaluate the job before starting. Here is a view of the alternator on the left. There are 2 mounting bolts, 1 corner bracket, 1 plugin style connector, 1 nut holding the B+ wire from the battery, and the belt.

Considering that we are working with the heart of the electrical system, the first and most important thing to do is to disconnect the battery before servicing the alternator.

All side post batteries have a 5/16″ or 8mm socket size to remove the battery cable.

Important Electrical Caution!!!

Always remember, when disconnecting the battery remove the negative terminal/ground cable first!!! This is to prevent any possible contact with surrounding grounds.

If you touch a ground no problems can occur if your removing the ground cable. On the other hand, if you contact a ground while removing the positive of a live battery you can short circuit the battery and do significant damage to the vehicles electrical system.

Note: Refer to the Replacing a Serpentine Belt and Tensioner post for how to remove the belt prior to servicing the alternator.

Alternator Removal

Using your ratchet and 15mm socket, remove the upper alternator mounting bolt.

Using the 13mm socket with extension, remove the nut and the alternator support bracket from the corner of the intake manifold.

Remove the lower alternator mounting bolt.

Pull back the protective boot and remove the nut for the battery cable. This is the cable that supplies voltage to the battery when the vehicle is running.

Remove the battery cable. This is why you should disconnect the battery. Eliminate the thought of your wrench touching a ground when removing the B+ cable from the alternator.

Lift out the alternator for removal, but be aware that there is still one more wire to disconnect. The only way to reach the connector is to lift out the alternator for access.

Unplug the 2 terminal connector. This is the power and ground wires that supply the alternators voltage regulator. (More on how the alternator works later)

Install the new alternator in reverse order and retest the charging system to make sure the new alternator is working correctly.
Refer to the Battery, Starter, and Alternator Testing post for a recap on how to check for proper operation of the alternator.

Estimate for Repair

(check with your local parts stores for current prices)
Parts to replace
Using aftermarket parts you can purchase a remanufactured alternator for around $80 and a new alternator for approx. $120.
Labor to replace
This job should cost approx. 2 hr. labor to test the charging system and replace the alternator. (Example: 2hrs.@ $80)
Parts and Labor
Re-man price/ $240
New price/ $280
Note: Factory parts and shop labor rates will be higher depending on type of repair shop and location.
Time to replace
This job should take even the experienced technician approx. 1 to 1.5 hours to complete

Purchasing a Tester

For those who continually invest money in tools for their job, here’s a piece of equipment that is a must have item. There are several different types of electronic charging system testers out there, this one is from Mac tools. These testers vary in price from $199-$399. The great thing about electronic charging system testers, is the ability to test and have results within 2 minutes.

Having the correct tools for the job is the most important part of diagnosing and repairing automobiles. Testing the battery, starter, and alternator is an area where improper diagnosis can be costly. With the correct tester this job can be diagnosed within a couple of minutes.

Before testing the battery or any other electrical issues, making sure there is voltage present with no corrosion or poor connections is the first step into diagnosis. For more battery and electrical maintenance tips refer to the following posts:

• Battery Knowledge
• Battery Cleaning
• Check, Test, and Replace a bad car Battery

Here is a step by step procedure on how to perform the 3 individual component tests that makeup your charging system. The tester used in this article is the Accuracy Plus tester from Mac tools.

1-The Battery Test

Hook up the battery tester color coded clamps. Red to the positive terminal of the battery and black to the negative terminal of the battery.

Once powered up, the tester will guide you through each step of testing.

The first thing the tester will ask is what the CCA or cold cranking amps are.

Input the amount indicated on the battery and press go. (Battery rating – 550 CCA)

This is the amount that the tester will “load” or take away from the battery to see if it meets the rated capacity.

After pressing go, the tester will load the battery two times within 20 seconds. Then it will show “battery good” or “battery bad” on the display and the actual amount of voltage and CCA’s tested. It’s that easy.

Battery condition good.

Test results, 12.6 volts and 510 cold cranking amps.

Battery Test Results

If this battery was bad, it would show low cranking amps. 510/550 is a good test result. If the voltage tests lower than 12.0 volts, the battery should be charged and re-tested.

2-Starter Test

Immediately following the battery test, the tester will instruct you to start the vehicle.

At this point the starter current draw will automatically be tested. (The starter results will show up at the end of the last test)

Starter Test Results

Good test results should be no more than 150 amps of current draw. Any amount over 200 amps could put excess drain on the battery. This could cause problems during the winter months and may even shorted the life of the battery over time.

3-Alternator Test

This is the final of the 3 tests for the complete charging system.

With the vehicle running, you will be asked to press go and increase the throttle to 1500 RPM. During this time (approx. 15 seconds) either jump in the car and rev up the engine…

…or look for the throttle cable on the engine. Increase the RPM slowly until the tester tells you to maintain the RPM.

The alternator will automatically be tested by simulating the maximum amount of load devices that could be turned on from your vehicle and record the output. It will also test the internal voltage regulator functions as well.

Here is the measurement of output from the alternator under a load test. (14.2 volts)

Alternator Test Results

Good results would be an increase in voltage by approximately 2.0 volts. (12.5 volts before starting, 14.5 volts running) The tester will show “diodes good” or “diodes bad” as a result also.

Final Results

When the test is finished, you will be instructed to turn the vehicle off. The complete evaluation of the charging system will scroll through for you to read. Here are the items tested:

• Battery load test – with voltage and CCA results
• Starter current draw test – with amount of amperage and voltage used
• Alternator output test – results with load and no load voltage and amperage output
• Alternator/Regulator – internal function test of the voltage regulator diodes

Final Thought

This tester is one of the most user friendly testers available. It’s also one of my favorite pieces of test equipment to use. If there are any electrical problems found on the vehicle being tested, the tester will tell you and stop with any further tests. This allows you to replace the faulty part and retest after the problem is fixed.

Here is a 2000 Ford Windstar with a 3.0 liter V-6. The customer concerns were… “when going to start the vehicle first thing in the morning, the car just clicks”. “Another strange thing that happened was the interior lights would turn on and off by itself”.

Safety First

When working around car batteries, always take precautions with handling batteries. Wear eye protection and gloves to prevent any debris or acid from getting on your hands or being rubbed into your eyes!!

Needed parts and tools for the job:

You will need the following new parts and tools to perform this repair;

• 1-Battery
• 1-Digital volt and amp meter
• 1-10mm wrench
• 1-1/4” ratchet with 5/16” socket
• 1-pair of safety glasses
• 1-pair of gloves

Price Comparison – How much you can save

Repair shop pricing
Parts-approx.$100-$120
Labor to diagnose and replace battery 1 hour($80)
Total cost-$180-$200 plus tax

Do it yourself
Parts-$50-$90 (from your local parts store)
Estimate time to repair, approx 30 min.
Total cost-$50-$90 plus tax

Verify the Customer Concern

Separate of turning the key to crank the engine, the best pre-test to perform is with a digital volt meter.

Locate the old battery and check the battery terminal ends for corrosion. (If corrosion is present, you’ll need to clean before testing)

Note:

Refer to battery maintenance for tips and advise on how to clean a battery .

Here’s an affordable digital volt and amp meter you can purchase for around $59 from Sears.

Turn the meter knob to the DC volt setting. Connect the red meter lead to the positive or + terminal of the battery.

Connect the black meter lead to the negative or – terminal of the battery. Here we show 3.1 volts in a battery that should show 12.5 volts.

This battery is more than 4 years old, so it’s not worth trying to charge just to see if the voltage comes up.

Note: 90% of all car batteries fail within 5 years.

Remove the old battery and replace with an equal if not higher strength battery.

Locate the Cold Cranking Amp rating on the battery. (CCA)

This one is a 550 CCA battery.

Install the new battery into the battery tray.

Install the positive terminal end and tighten the 10mm nut.

Install the negative terminal end and tighten the 10mm nut.

Install the battery hold down and tighten with a 5/16″” socket and ratchet.

Test the new battery with the volt meter the same way you tested the old battery.

Start the engine and watch the voltage on the meter. Before starting, the voltage should be at 12.5 volts. When running the voltage should be at 14.5. The 2 volt increase is a sign that the alternator is charging.

What you’ll need for this fix / car repair tutorial

You will need the following new parts and tools to perform this repair;

• 1-Blower Motor Resistor
• 1/4″ nut driver
• 7/32″ socket
• 1/4″ universal/wobble

With a short explanation and basic understanding of electrical functions in the automotive world, you can understand how and why these parts fail for future reference. The car being used in this article, is a 2002 Pontiac Grand Am

Price Comparison – How much you can save

Repair shop pricing
Parts-approx.$60
Labor to diagnose 1 hour($80), labor to repair 1 hour($80)
Total cost-$220 plus tax

Do it yourself
Parts-$30 (from your local parts store)
Estimate time to repair, approx 30 min to 1 hour
Total cost-$30 plus tax

Step 1 – Identify the problem

Lets start with speed number 5.

The battery voltage is at full potential when you switch it to speed #5 (approx-12.5 volts). In this position the blower motor runs at high speed as fast as it can.

Reference Note

For a better understanding of electrical diagrams you can refer to automotive electrical theory in Automotive Electrical 101 – Part 1

Follow the silver line through the wiring schematic. This is the path that the voltage is traveling through setting #5/high speed.

When switching to speed #4 the voltage goes through a resistor before reaching the blower motor. This resistor takes away approximately 2 volts. Now with 10.5 volts supplied to the blower motor, it runs at a little bit slower pace. It blows fast, but noticeably slower than speed #5.

Note:This illustration is a 4 speed blower circuit. The point is to show you how the speeds are controlled by resistors.

Speed #3 adds one more resistor in series for the circuit. Now take away 2 more volts. Now the blower motor is running at 8.5 volts. Each speed is supplied with a smaller amount of voltage, thus allowing the blower motor to slow down.

Speed #2 and speed #1 work on the same principle.

If you take a circuit and put a resistor in the path of current flow, you will restrict the path, only allowing a certain amount of voltage and current to be supplied to that load device. In this case, the blower motor is our load device. Now you can see that when a blower motor resistor goes bad, you can lose your lower speeds and still have the highest setting.This should give you an understanding of how the voltage is controlled in a blower motor circuit.

Locating the Resistor

GM usually puts the blower motor and resistor next to each other. Nine times out of ten, both of them are accessible from inside the car. The blower motor and resistor in this Grand Am are mounted in the bottom of the heater box in the passenger footwell area.

Start by removing the lower trim under the glovebox.

The attaching screws can be removed with a nut driver and a 7/32″ socket.

Once the 2 screws are removed, pull out the panel.

Note: The only tools needed for this job is the 1/4″ nut driver, 7/32″ socket, a 1/4″ universal/wobble socket, and a light to help see the work area.

Position the passenger seat as far back as possible. This will allow you enough room to lay in the floor area to see and work while replacing the resistor.

Here is the view with the panel removed. The round component is one end of the blower motor.

The black and blue electrical connector behind the motor is where the resistor is located.

In order to access removing the resistor, the blower motor will have to be removed first.

Replacing the Blower Resistor

The alarm module will need to be removed. Pushing the module to the right allows it to slide out of it’s bracket.

Don’t bother unplugging the module, there’s enough room to work around it hanging down.

Remove the 3 hold down screws.

Use the same nut driver and socket, but add the wobble attachment.

With the blower motor screws removed, pull the motor straight down for removal. Be cautious not to pull the motor to the side until the blower cage clears the housing. This is to prevent damage to the cage assembly.

Unplug the blower resistor

Remove the resistor mounting screws.

Pull out the old resistor.

Here is what a blower resistor looks like.

Compare the old resistor with the new one to make sure they look alike.

Compare the electrical terminals also, and make sure they are identical.

Install the new resistor and screws.

Plug in the resistor.

Reinstall the blower motor.

Be sure to test the operation of all the blower speeds before reassembling the lower trim.

If you need help locating and pricing parts for your own car refer to Locating a good source to purchase parts

How do you determine how a electrical circuit works and how to test it? In the first section you’ll learn basic electrical theory and how to trace current flow in an automobiles electrical circuit. I will also explain wiring diagrams and how to read them.

There will be many up and coming articles about tracing and repairing electrical circuits within today’s vehicles so please make sure to check back for more.

Starting thought

Before attempting to diagnose or repair any type of electrical circuit you need to understand and know how electricity works in today’s automobiles.

I could talk all day long about electron flow theory, but with simple explanations of how, where, and why electricity operates, I will teach you what it takes to understand and diagnose simple automotive circuits. Here is a crash course on how it works.

Define Electricity:

Electricity is a controlled movement of electrons from one atom to another.

What does this mean and how does it relate to automotive technology?

What this means is, anything that is electrically operated on your vehicle operates by electrons moving through each circuit. When you have a power source like a car battery, you have a way to make these electrons unstable and wanting to move about. These unstable electrons are now your electrical source to power up objects that you can use in today’s cars. Electric motors are everywhere in your car. These motors operate your windows, sunroofs, seats, wipers, heater blower, cooling fans, and even the starter on your engine. These are only a few to mention.

I’m going to use these objects I’ve mentioned, and put together a circuit that is something you will see on today’s cars.

Basic electrical circuit

• An electrical power source
  (the car battery)
• A load device
  (something to use electricity to perform a working task ex; bulbs, motors, etc)
• A control device
  (this would be a switch or control unit that creates an open within the circuit)
• A path for the voltage and current to flow between these two objects
  (this would be the wiring to complete the circuit)
• A protection device
  (a fuse or circuit breaker, this would prevent an electrical meltdown if something failed in the circuit)
• Connectors
  (these allow sections of the circuit to be connected together and are easy places to test within the circuit when problems occur)

Electricity always leaves the battery positive side and flows to the load device which uses the voltage only, allowing the current or amperage to return back to the battery negative side completing the entire circuit. If there are any breaks or opens in the circuit, the voltage will only be present up to the break and not allow the circuit to operate. This is why it is important to have a good ground on electrical circuits. The ground paths use metal or frame areas through out your vehicle and return back to the battery.(We refer to this as chassis ground)

Plan ahead

Before doing any type of on car diagnosis, you should have a plan of attack. This means map out your electrical testing steps on a wiring diagram. Just like taking a road trip or vacation of some type, you probably wouldn’t just take off on a long trip without knowing where you are going ahead of time.

Every component in a car has an electrical diagram to show the circuit layout. Over the next few electrical articles I’m going to show different circuits, explain how they work, and list all the symbols used in these circuits. Here is a horn circuit, I’ll walk you through where the power comes from all the way through the circuit wiring, horn, and back to the battery ground.

Typical wiring diagram

Electrical circuit breakdown

The first thing to always remember is the power source always starts at the top of the page and flows down. Here you can see the text Hot At All Times on the left. This means no matter which position the key is in, off, position 1, 2, or cranking there will always be battery power present to this circuit.

Just below that you will see Fuse 13 /20A. This means the protection device in this circuit is a 20 amp fuse in position 13 of the Under hood Fuse/Relay box. (Note the dashed line around the fuse box, this represents a partial view of the box and there is more to it)

In the center is the Horn Relay. The relay is a electromagnetic switch that controls the power to the horns. The coil is on the left of the relay and the switch is on the right. When the coil is energized, it’s magnetic field pulls the switch and sends power to the horns. Notice the box around it is solid. This means it’s a full view of this component. Just above the relay there is a dot where the two wires split from the original wire, this is a splice in the wiring that is a soldered or permanent connection, this doesn’t come apart like a connector. The relay is located inside the Relay Control Module, which is inside the Under hood Fuse Box.

Note the 3 wires coming out of the fuse box and going down. They have letter and number designations next to them. (I9, M5, M6) This is for reference when trying to find their location on the car. The I and M are different connectors, and the numbers represent where the wire terminals are in the connector. (terminal 5 for one wire and terminal 6 for the other)

On the left of the wires are designated color codes for the wires. GRN/YEL is a green wire with a yellow stripe. BLU/RED is a blue wire with a red stripe. In the middle of the GRN/YEL wire is a C401 /18. This “C” always represents or stands for connector. The 18 represents the terminal inside this connector. C405 is another connector and E1, F1, and G1 are the terminals inside the connector.

This section shows the GRN/YEL wire going through 2 components. The first is connector/terminal B1 of the partially viewed Cable Reel. The cable reel is a special coil of wire that rotates within the steering wheel. The wire continues out of connector/terminal C1 on to the partially viewed steering wheel.

The other two BLU/RED wires continue on down the diagram to the next component.

Once inside the steering wheel, the GRN/YEL wire changes color to a BLK wire. (black) This wire continues on to the horn switch (full view) which is inside the partially viewed steering wheel. At the bottom of the steering wheel there is a dot with 3 small lines attached horizontally, this is the symbol for a ground.

On the right, the two BLU/RED wires continue on to the horns. One low tone horn and one high tone horn that have separate grounds.

Now that I’ve described each symbol and component on this diagram, I’m going to explain how the voltage and current flows through the circuit.

Understanding what electricity is

All automotive electrical circuits have 3 things that are constantly talked about, voltage, current, and resistance. These 3 things are what it takes to operate a circuit. The direct relationship between voltage, current, and resistance is most commonly referred to as ohms law. (more on ohms law later)

Voltage is referred to as EMF, the Electromotive Force that supplies electrical energy to the circuit. Coming from the battery it’s the electrical pressure that pushes current through the circuit.

Current is the electrical flow within the circuit. What is flowing? Electrons!! Lets go back to our definition of electricity; a controlled movement of electrons from one atom to another. Electrons are the current flow. All matter is composed of atoms which are full of electrons that can be stable or unstable depending on their environment. In this case, our battery is an electrochemical device that is designed to make electrons unstable. (more about battery’s later)

Resistance is a restriction to the current flow. Using the horn diagram, the horns are the load device in this circuit. They restrict the current flow. As voltage and current are traveling down this circuit to the load device, they are searching for a path to ground. The horns operate by using the voltage to perform a task. A horn is basically a loud speaker. When activated, the horn will use the voltage and allow the current to flow back to the battery creating a constant flow of electrons in a complete loop or path called an electrical circuit.

Wiring Diagram Review

In reference to the horn circuit diagram, here is how the circuit works. The battery power supply is hot at all times through the under hood fuse box and fuse 13 to the horn relay. The power supply feeds both the coil and the switch inside the relay. Here is where I make you think. The coil power on a working circuit stops here because in order to energize this coil to make it a magnet for pulling the switch, we need to ground the other side of the relay coil. If you follow the GRN/YEL wire through the rest of the circuit, the horn switch that you push to honk the horn completes the path to ground. Now with the relay energized, the switch is pulled closed to send power down to the horns that are already grounded, waiting to sound off. This is how the horn circuit works.

Key Electrical Terms

(Key terms in bold throughout this post)

Note:

Now that your through with Automotive Electrical 101-Part 1, you can refer back to System 101 for more automotive topics

Coming Soon

• Automotive Electrical 101-Part 2 (Digital multimeter usage)
• Automotive Electrical 101-Part 3 (Testing inoperative and shorted circuits)
• Automotive Electrical 101-Part 4 (Measuring voltage, current and resistance in a circuit)