Electric Problem

I could have posted this in the audio/video forum I guess, but it doesn't get as much exposure as this thread does. Anyway:

I'm having a problem with my 1993 T100. I have a guess, but I sure hope I'm wrong. I think it may be my alternator

My problem is with my electrical system. My truck has started most days, except once when it was super cold (-50f). But, it usually starts pretty slow. When I give it some throttle (RPMs go up to about 2000-3000rpm..ish), my headlights get way brighter, but the main problem I have, is my sub. I have a DUAL ALB10, and when I give my truck a little gas my sub shuts off.

It did this when I first got the truck, however it got better for a while. I haven't touched a thing, and it has started acting up again. I'm just worried though, I bought a new battery, my terminals are clean, the only thing I haven't done is checked my voltage because I don't have a volt meter (I know, I need to get one).

Anyone have any ideas? The sub is really annoying, but my lights dimming when I step off the throttle really bothers me. Any help would be appreciated!

 

Undo the sub, does the problem still exist?

 

Yup.

 

Have you put a voltage meter on the battery while reving the motor? You may see the voltage dropping out on the meter, thus shutting down the subs.

Edit:Just reread that you have no meter. With that said, meters are stupid cheap these days and you can get them anywhere. You will be money ahead to have one.

 

The headlights look dim in your sig pic

You could even stop by auto zone and have them put the meter on and check for you. If you are the least bit handy, you could remove the altinator and have them check it for you. The altinators come out real easy.

 

Haha, that picture was taken during the time period when everything was working pretty good. It was taken with my iPhone so that might be why they look dim.

But yeah, I def. need to get a meter. I'm just confused as to why my sub is shutting off when I put my foot on the gas...that should produce more voltage, keeping my subs on. At least if I took my foot off the gas and my sub shut off it would make more sense.

 

You say the lights get brighter when revved? I'm wondering if there is a voltage regulator problem with that altinator? The subs may be protecting themselves by shutting off when they sense excessive voltage.

 

Deff sounds like a voltage reg problem, your sub is probably cutting off because the amps being either over or under powered and its shutting itself off

 

Thanks for your guys' feedback. This morning when I came to school it was completely fine, lights didn't brighten or dim, sub didnt shut off, etc. didn't change a thing either, just left my truck overnight. Thoughts?

 

Still address the issue could be a short somewhere

 

Okay now I'm super confused. 15 minutes after I wrote that last post I went out to lunch with a friend, and when I left school my truck wasn't right. It had the problem again. When I left to come back to school, it still had a problem. When I left school a couple hours later, at about 3 o'clock, it was completely fine, sub didn't shiut off, nothing dimmed, it's weird.

 

Better check all the grounds. Body ground could have corrosion and is intermittantly grounding.

 

You can buy a digital multimeter set it to 20 volts dc test battery without truck running, then start truck test battery again, voltage should read more with truck running, if not it's a good bet your alternator is failing hope this helps. 2to 2/12 volts more with truck running would be in the ok range. This is assuming your battery is up to par. Sounds like the voltage regulator in your alt is going bad, these are internal regulated.

 

I will most likely end up getting my alt tested. If it's bad, I'll replace it...found them online for around $120, thought it was going to be much more expensive. Thank you!