How Much Does An Alternator Repair Cost?

An alternator repair costs around $375 – $1,100. 

These numbers will vary based on the auto parts needing repair or replacement, car model, and labor cost. It takes about 2 hours for an alternator replacement — about as long as a driveline repair and a little quicker than a clutch repair.

The estimated price for parts (including a replacement belt) can range around $290 – $600. And depending on where you get the auto service, labor can cost between $85 to $800.

You could also ask your mechanic for a remanufactured or rebuilt car alternator if a new one is too costly. Make sure your purchases have a warranty to cover any potential problems.

How Urgent Is An Alternator Repair?

If the alternator fails, the battery doesn’t charge, and the car won’t function as it should. Problems with stalling and starting may leave you running late. Specific safety components like the headlights might not work when you need them. 

Also, a faulty alternator can damage certain electrical systems by overcharging or undercharging them. You could end up with additional repairs if you leave the bad alternator unresolved. 

That’s why you should get quality electrical systems inspections from a reputable auto repair service when you notice bad alternator symptoms. It can even be a good idea to check an old alternator regularly, like when getting an oil change or your tires serviced for tire rotation.

Symptoms Of A Failing Alternator

Here are signs that your car may need an alternator repair:

• Dead battery: A defective alternator won’t charge the battery while the engine is running.
• Hard starting or stalling engine: An underpowered battery (because the alternator isn’t charging) will have trouble starting the car.
• Dim or too-bright lights: A damaged alternator may deliver either too little or too much power to the headlights. 
• Electrical system concerns: Electrical accessories like your radio, power windows, and air-conditioning might begin to falter with a bad alternator.
• Whining or squealing noises: A misaligned alternator pulley or worn-out pulley bearings can generate odd noises.
• A burning odor: Burnt smells can point to an alternator pulley or drive belt problems.
•  Lit dashboard warning lights: A lit battery light, check engine light, or charging system light can all indicate alternator issues.

4 Alternator Repair FAQs

Here are answers to some common questions on alternator repairs:

1. Can I Drive With Alternator Problems?

Yes, but only for a short while before the battery fails, then you’ll need an alternator repair. 

2. How Often Do I Need An Alternator Repair?

An alternator can generally last for about 150,000 miles or 7-8 years before needing replacement. 

3. How Do I Load Test An Alternator?

To load test your alternator, you need a voltmeter or multimeter. 

Here are the steps to take:

1. Battery assessment: With the engine turned off, connect the multimeter leads to the battery terminals — red to the positive terminal, black to the negative terminal. A good, fully charged battery should measure between 12.6 -13.2 volts. 
2. Alternator assessment: Turn on the engine. With the engine running at around 1000 RPM, the multimeter voltage should stay within 12-14 volts.
3. Load engine: Start turning on accessories (like the headlights, radio, and windshield wipers.) The voltage shouldn’t drop under 12V or go above 14V.

If any readings are out of range while the engine is running, your alternator could be problematic, and you may need a car repair. 

4. How Do I Replace An Alternator?

Here’s how a professional mechanic would replace a failed alternator:

1. Disconnect the negative battery cable.
2. Disconnect the cable connections from the back of the alternator. 
3. Remove the drive belt from the pulley by loosening the belt tensioner.
4. Once the belt is off, unfasten the mounting bolts connecting the alternator to the bracket.
5. Remove the old alternator from the bracket.
6. Compare the new alternator with the old alternator and check whether everything matches, including the mounting bolt holes.
7. Install the new alternator and tighten the mounting bolts with a ratchet.
8. Slip the drive belt back in position by using the tensioner arm and reinstall all cable connections.
9. Review the installation and test the alternator output using a multimeter. 

Tips: Ensure the battery is fully charged before installation. Using the new alternator to charge a low volt battery can damage the alternator.