Alternator problems? Do a Fusible link test first

are you having battery charging issues but have changed the battery and alternator? check the fusible links. the usually blow once they get corroded enough over time

Check these guys out:

Diagnosing Alternator Problems - EricTheCarGuy

How to Test an Alternator - ChrisFix

[repeat_v]

THIS VIDEO SAVED ME A MASSIVE HEADACHE! Turns out the positive battery terminal (which i bought new) was bad because my alternator wasnt receiving the proper voltage. once i swapped the terminal, all life came back to the car. You're truly a life saver!

[chadbrewer]

Do yourselves a favor too; check the grounds on your engine block!!! About tore the rest of my hair out and washed this overland with 2 gallons of diesel and a road flare! Both wire harness mount bolts on the passenger side of the block removed, terminals sanded, rust converter sprayed and reinstalled everything. Jeep started strong first crank and I’m seeing 13.89 on the multimeter with engine running. Check all of your grounds….

[CryptCrossfre]

I think you have helped me find my issue that I have been scouring here to find the a better answer to why after a new battery and rebuilt alternator still getting the "Service Charging System" for my Impala. I had heard about this fusible link but had no idea where to look! This is start in the next direction! Thank you!! You are appreciated!!! Great short video!

[jpol]

Great tip. That's what we need more of....the unusual items that usually aren't the issue. Thanks.

[bobbofly]

"& you can't just splice it." Well... you can, it's just a really bad idea, long term. Fuses/links are there for a very good reason. (🔥)

[AristidesIoannides]

Good video and nice troubleshooting task to add to your troubleshooting toolkit. One note, when you measure continuity with a VOM and get 0 OHMS, there us NO resistance. In fact, you want a closed circuit with little or no resistance in your fusible link and the connection between the B term on the alternator and the battery + post.

[Normanb]

You know what you are doing... I thought you may be able to answer my question. I am wondering about the fusable link as my alternator is not working. I used a multimeter and got continuity from alternator plug pins to the battery terminal connectors. Should that mean that the fusable link is intact? It wouldnt seem like that plug could handle the current put out by an alternator so I may be wrong

[MysLed]

*2:00* Cable on the B post of the alternator, is that the negative? Because when you do the same test on the good alternator, you switch the + & - with that test.

[sickofliberals]

I'm getting ready to try this on my dodge, just put new alternator on with new battery and still no charge so hopping this works, wish me luck

[squitzy]

Good video but when the meter goes from 1 to 0 it means that there is NO resistance, the circuit is closed and current will flow through it. The 1 on the meter indicates infinite resistance, the circuit is open and no current will flow. Otherwise, thanks for the good info!

[SavageThrifter]

That fusible link in my car blew but now I have to found what keeps blowing it. I wish there was a video on youtube about tracing the positive and negative battery terminals to the starter and transmission but doesn't seem super hard once I actually get my car back, maybe I'll get lucky and be able to see it visually myself

[mitchlee]

I 91 Toyota Land Cruiser having same problem so I’m going to effort chasing out that fuse able wire from the alternator to the battery I just need a place to start and your video gave me that so thank you posting that: I don’t give you a heads up on how it works out it’s going to be a few days as I am leaving troll trip commercial fishing it’s what I do... ;)

[Emmanuelchavez-mpsw]

You just saved me from replacing an ecu👍

[tweed]

i have a big black wire coming from the back of the alternator screwed on does it go to positive or negative on battery? I have it on negitive and dash gauge for battery shows just a quarter way instead of half way. I put in new battery and the alt but something not right. 99 gmc jimmy.

[Jonathan-dor]

whats your voltage under load, turning on lights and heater ect ect

[nigelmahood]

Thank you. Never even thought about that.

[rioterry]

Your video didn't show nothing. Im trying to find my fusible link so I can check it . I'm trying to see if that's why my battery light stays on and my gauges stopped working. The truck still runs, no turn signals tail lights or radio.

[MrMeasureTwice]

I appreciate the details, but using the wrong words when discussing electricity can get someone killed - no, seriously, it can. Please understand that every time you said RESISTANCE you were using exactly the opposite terminology - when the meter goes to zero, or nearly there, it is NO resistance, or you could say that there is CONDUCTIVITY, which is the correct terminology.


Overall, a good video, bad verbal explanation of resistance vs. conductivity.


NOTE: to those who also called Steve on this, but you said 'conduction', you were nearly correct, but conduction is more commonly used when discussing the conduction of heat.

[spelunkerd]

At the beginning of the video your multimeter dial was rotated to the icon for testing diodes, it is not exactly the same as the ohm test option that you want. Instead of measuring ohms, it is measuring the tiny voltage drop across the two leads when a small voltage is applied by the meter. Check your multimeter manual for more detail, it is a setting only useful for testing diodes.

[tomthumb]

If the fusible link is burnt then you will not have battery amperage at the alternator? And PCM controlled alternators use a fusible link?