In this video, young mechanic Aiman will show you how to diagnose and test to see whether it is the battery or the alternator that's causing you not to be able to start your car's, trucks, minivan or SUV engine. Obviously, there are many other ways to test if your alternator or battery is bad when your car dies, unable to start or there is a warning indicator light on your dashboard.

Here are the #ᴬᴰlinks to tools, parts and accessories you may need to perform this repair:

1. https://amzn.to/3Vy8XUC | AstroAI Multimeter Tester 10000 Counts TRMS Auto-Ranging Color LCD Screen Digital Volt Meter, Fast Accurately Measures Voltage Current Amp Resistance Continuity Duty-Cycle Capacitance Temperature
2. https://amzn.to/4alnTJU | NOCO Boost Plus GB40 1000A UltraSafe Car Battery Jump Starter, 12V Battery Pack, Battery Booster, Jump Box, Portable Charger and Jumper Cables for 6.0L Gasoline and 3.0L Diesel Engines, Gray
3. https://amzn.to/4cEydPk | BT100 Car Battery Tester 12V Load Tester Automotive Alternator Tester Digital Charging Cranking System Tester for Car Truck ATV SUV Boat Yacht

Or Click on Amazon link here and search for what you need: https://amzn.to/3xIOsqg

By the way this is Uncle Lan Roslan Omar's Honda CRV SUV with special Connecticut vanity plate spelled Malaysia because he is Malaysian. He appears in my videos sometimes.

We have a published a video on a simple and easiest way (although not recommended by professional mechanics or technicians) to test to see if your alternator is bad. Click to see that video here:

   • How To Perform Simple Test Whether Al...  

That video was actually a part of a longer video on "What Does Battery Light Symbol Indicator On Your Dashboard Mean, What To Do & How To React". Watch that video here:    • Why Battery Light On Dashboard Stays ...  

Open the hood and start the car. While the engine is running, remove the negative cable from the battery. If the vehicle stalls or dies, the alternator is likely bad. This happens because the alternator is not generating enough electricity to keep the engine running on its own. If the car continues to the run, the problem may lie with the battery. However, be careful when using this method. Do not rev up the engine.

[Caution] A good alternator may indeed keep the engine running, but it was never a good test. In the pre-computer days, you could pull it off without damaging anything. Today, you risk frying every electrical device in your vehicle.

Our test involved using a multi-meter which you can get nowadays really cheap, under $30. We recommend the AstroAI Digital Multimeter above. With the engine off, battery voltage should be between 12.5 and 12.8 volts (assuming the battery if fully charged). If it’s below that, charge the battery with a battery charger before you conduct the test.

Then start the engine and check for increased voltage. Connect the meter leads to the battery terminals and look for around 14.4 volt (or a range of 13.8 to 15.3 volts with the engine running, lights and accessories off). That means the alternator is pumping out the juice. If you see higher readings, chances are the alternator is good (more sophisticated testing equipment is needed to detect an open or shorted alternator diode).

Another simple & easy method to determine if your alternator is dying are the headlight test and the battery test. The headlight test is quick and easy, and should be performed outdoors to ensure that you don't have a carbon monoxide buildup inside your garage. To perform the headlight test, start your car and turn on your headlights. With the vehicle in park, press on the accelerator while a second person observes the headlights. If the headlights flicker, dim or get brighter when the accelerator is pressed down, your alternator may be bad. No change in headlight brightness indicates that your alternator is likely fine.

Thanks for watching, please check our other DIY auto repair tutorial & guide videos on EyeOnAiman's channel. Other cars Aiman have worked on includes Honda Accord, Civic, Insight, CR-V, Hyundai Santa Fe, Elantra and Toyota Prius Hybrid.

Obviously, Aiman's auto repair videos are mostly designed for entertainment purposes. Aiman is not a professional and not a certified ASE mechanic. The videos should always be used only as a guide.

You can watch all of Aiman's auto repair videos in the following playlist:    • How To Remove Alternator Hyundai Sona...  

This video is presented to you by Aiman-Imran Anuar. You can watch more of #Aiman_DIY_Auto_Repair videos on #EyeOnAiman Youtube Channel & Facebook Page.

Note: This video is NOT sponsored. Some product links are affiliate links which means if you buy something we'll receive a small commission. As an Amazon Associate we earn from qualifying purchases.

Recording Date: August 23, 2023
Video URL:    • How To Diagnose Whether Battery Or Th...