ColterDC

Can someone tell me or show me where I might find the approximate amount of voltage/watts being used by my car with the lights, heater, radio, etc on?

The car is a 96 mustang GT with the mach 460 stereo system.

It has a 130 amp alternator, but I'm getting really bad voltage drops since adding an aftermarket sub and amp. Wondering if the car was close to max with just the stock equipment and that the addition of that aftermarket equipment was to much for my alt to keep up with or if my battery or alt are going out and need to be replaced.

Thanks!!

MU71L4710N

how many watts is your amp?

and before you worry about replacing anything i would go ahead and do what they call "the big 3" or whatever. its replacing all the cables running from your alternator to battery to ground with thicker, heavier guage wire. it allows your electrical system to charge much more efficiently and can reduce light dimming and such when your at a stop.


pulled out of the sticky in the audio section...

The BIG 3
[ol][*]The Altenator to the Battery[*]The Battery to the Chasis[*]The Engine ground to the Chasis[/ol]
The changing of these 3 wires to a larger guage can not only help your electrical system, but it can benifit you in any competition you may enter.

Keep this in mind when deciding what awg to choose, always look at the power charts of your amp, and if it requires 4 awg then use no less than 4 awg. Use 2 awg if you can, and if you are feeling nutty, go all out and use 0/1.

ColterDC

Already did the big 3 with 0/1 gauge.

The amp is only 400 RMS watts. You wouldn't think that reasonably small increase in voltage would cause such a huge voltage drop.

I'm not sure if the cause is a bad ground, overworked alternator, battery with a dead/dying cell or a dying alternator.

a_penquin

Im guessing since you have done electrical work before you have a multi meter. Set your multi meter to the best setting to read 12V DC. Start the car without accessories on. Place leads across the battery terminals to get a reading, it should be around 14.4v charging. Wait 5-10min to let the battery charge. Take second reading, 12-13v. Turn on your stereo and have the amp on. Check for drops and spikes as the sub hits, also turn on accessories one at a time to find the limit.

I can already tell you your over drawing the system with everything on due to the lights dimming when the sub hits. If your charging voltage is not around 14.4v then its your alternator, if it never drops after the charging cycle is complete it could be the battery being the issue. If anything this will tell you your charging system limits if you are not upgrading the alternator.

04goat

sometimes the voltage surges like that on certain vehicles! sounds like you have one. my son had one that did the same thing as yours, he went to Autozone and bought one of those amp boosters. it is a voltage regulator about 8 inches long and 3 inches accross. When the base hits the regulator puts out the amps needed to make the equipment perform properly. but be very careful as this thing can hurt you!
After you have charged the regulator it will hold the charge for a long time with nothing hooked up. But used in the proper way it will solve your problem. and my son had 2000 watts with some very hugh 18's. he had more than that. and the regulator is not that expensive either...

a_penquin

That regulator you talk about is actually a capacitor. It stores energy for the amp to feed off of and give a more constant feed to the amp.

http://www.google.com/products/catalog?q=capacitor&oe=utf-8&rls=org.mozilla:en-USfficial&client=firefox-a&um=1&ie=UTF-8&cid=3558972903045338037&ei=lo0BTdqMF8GqlAf9suDOC A&sa=X&oi=product_catalog_result&ct=result&resnum= 4&ved=0CF8Q8wIwAw#

04goat

yep exactly! if the op will go buy the capacitor it will solve his problem!