High output alternator help

Jimbo1227

CarAudio.com Newbie
May 5, 2021
1
0
What’s up all. I installed a mechman 370 on my f150. Now I’m getting a charging system light and my headlights are flickering even when radio and everything are off. My voltage also doesn’t stay steady even at idle it goes up and down from about 13.3 to 15.4. No idea what the hell it is. I’ve tried everything I could think of. Also when I put the stock alternator back it everything goes back to normal 🤷‍♂️🤷‍♂️🤷‍♂️ So if anyone has any ideas. It would be appreciated. Thanks
 

Fishchris

CarAudio.com Recruit
May 15, 2021
68
9
What’s up all. I installed a mechman 370 on my f150. Now I’m getting a charging system light and my headlights are flickering even when radio and everything are off. My voltage also doesn’t stay steady even at idle it goes up and down from about 13.3 to 15.4. No idea what the hell it is. I’ve tried everything I could think of. Also when I put the stock alternator back it everything goes back to normal 🤷‍♂️🤷‍♂️🤷‍♂️ So if anyone has any ideas. It would be appreciated. Thanks
I have an F150 with a 320 amp alt... No problems.
Wish I could say exactly what was going on with your setup, but I'd call Mechman and discuss that with them if I were you. I think they have pretty good customer service over there, and they would totally love to help you get that fixed, vs. you sending it back to them 🙂👍
 

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,587
1,180
What’s up all. I installed a mechman 370 on my f150. Now I’m getting a charging system light and my headlights are flickering even when radio and everything are off. My voltage also doesn’t stay steady even at idle it goes up and down from about 13.3 to 15.4. No idea what the hell it is. I’ve tried everything I could think of. Also when I put the stock alternator back it everything goes back to normal 🤷‍♂️🤷‍♂️🤷‍♂️ So if anyone has any ideas. It would be appreciated. Thanks
Do you have an external voltage regulator?
 

metalheadjoe

Unapologetic prick
10+ year member
Oct 21, 2007
1,348
666
Oem alternator works fine; aftermarket alternator causes problems... sounds obvious to me.
 

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,587
1,180
Oem alternator works fine; aftermarket alternator causes problems... sounds obvious to me.
If he has an external voltage regulator, and it's not getting enough amperage, that could very well cause his flashing headlight problem. I know from very painful personal experiences. Thanks to the horrible customer support of Excessive Amperage, I had to figure out how to fix this problem myself, with my 300 amp alt on my Explorer.

I had to run 2 10 or 15 amp 5 pin relays to my external voltage regulator, and I had to use 2 8 gauge wires and stack them on top of each other for both power and ground, it was quite a stupid and poor design, honestly. Why does a thing that supposedly draws 10-15 amps of current need essentially like 30 amps of current? A lot of these ext voltage regulators are the same model, and it seems like many companies should actually explain how to properly install them, which a lot don't seem to. There should be a manual that they send with the alt and ext regulator. The external voltage regulators, many that I've seen, leave a lot of room for improvement.

Like my alt was a super good performing alt, when the damn regulator worked properly. Took me and my shop friend who is a certified car alarm installer (very difficult work) something like a couple of months to actually figure out the regulator powering was the problem. Ugh, dude, it was so frustrating. I was 19 when I figured this problem out. I was just lucky enough to have experienced people around me and have access to a shop full of testing equipment and tools.
 
  • Like
Reactions: metalheadjoe

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,587
1,180
If your headlights are flashing, your alt is probably only putting out 1/2-2/3's of it's actual power, because it's not being communicated with properly via the FIELD wire, which is what the external voltage regulator is using for controlling.

And a lot of cars absolutely hate the signal that external voltage regulators send back through the field wire into the car's computer. I just had to disconnect my FIELD wire from the Explorer's computer, because my battery light would flash on and off over and over into infinity lol. I could never figure out how to make the voltage regulator make my Explorer's computer think everything was ok, because it was. Alt worked very well, so idk. I know a lot of other people have issues with aftermarket alts like I have described.
 

metalheadjoe

Unapologetic prick
10+ year member
Oct 21, 2007
1,348
666
If he has an external voltage regulator, and it's not getting enough amperage, that could very well cause his flashing headlight problem. I know from very painful personal experiences. Thanks to the horrible customer support of Excessive Amperage, I had to figure out how to fix this problem myself, with my 300 amp alt on my Explorer.

I had to run 2 10 or 15 amp 5 pin relays to my external voltage regulator, and I had to use 2 8 gauge wires and stack them on top of each other for both power and ground, it was quite a stupid and poor design, honestly. Why does a thing that supposedly draws 10-15 amps of current need essentially like 30 amps of current? A lot of these ext voltage regulators are the same model, and it seems like many companies should actually explain how to properly install them, which a lot don't seem to. There should be a manual that they send with the alt and ext regulator. The external voltage regulators, many that I've seen, leave a lot of room for improvement.

Like my alt was a super good performing alt, when the damn regulator worked properly. Took me and my shop friend who is a certified car alarm installer (very difficult work) something like a couple of months to actually figure out the regulator powering was the problem. Ugh, dude, it was so frustrating. I was 19 when I figured this problem out. I was just lucky enough to have experienced people around me and have access to a shop full of testing equipment and tools.
Your personal experience outweighs my speculation.
 

Buck

Why so Sirius?
5,000+ posts
10+ year member
May 19, 2008
28,587
1,180
Your personal experience outweighs my speculation.
I just know how much of a pain this can be to figure out, especially if you're just doing your personal vehicle for the fun of it. Makes you want to throw stuff and destroy it, it's that kind of frustration 😂
 

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Latest threads

Latest classifieds