I've been having lots of weird problems lately...mostly since i put in my system. ive been having a few problems trying to get it started. starting a week or so ago i parked the car. came back went to start it and turn it to the on postion and my volts only read at 8. so i let it sit a little bit. then she starts right back up (with the volts reading just above 14). so today i go to start it and when i go to turn it over i hear a click then it dies. turn it to the off and then back to on and the volts are real low. turn it off again and on again volts are normal again. i did this 3times before it started. i get it started take her for a drive and i noticed that if i turn up my stereo up loud or turn my subs on the headunit turns off then comes right back on.

i think its the alt. anyone have any ideas?

 

when you start seeing low volts, wiggle the ignition key. See if the voltage changes

 

bad battery or bad alt.

If the head unit is dieing then the problem is probably low voltage... what is the voltage at when this happens (it should be always above 12.6 volts- if it is dropping under that the car is only running on the battery).

 

i have an alt ill sell ya

 

Try buying a bigger battery... that should solve ya problem.. get a gel battery.. i heard they last longer.. if that dont work... get a nother alternator... i suggest the battery..(cheap way out of it)... if that dont work.. at least ya got a bigger battery and a new alternator for superb power..

 

You know mark, I had the same problem when I was running an in dash cd changer. Power would just cut out.

I ran knew wire from the battery through a relay and it worked fine since. I don't have the stereo any longer, but it put that stock wiring into question IMHO.

me two, double pullies even

 

icemark sounds completely right this happen to one of my cars when i turned it up to high and when it hit big bass parts im having this same problem now with my truck i unhooked the wire that gos from the amp to the battery but thats not the problem so i guess something in my headunit is on all the time draining the battery and i put new battery and alt in it

 

im buying an fd alt. so i geuss no worries. but just for kicks i added a ground from the (-) neg batt terminal to the frame and im not having any problems. all i can say is, what the hell?

 

to test a power drain you disconnect your negative battery terminal and put a test light betweent he battery and the terminal and if it lights up then you got a drain. If it doesnt light up then your fine. To check where the drain is comming from you go pull the fuses one by one to see which one shuts the light off.

 

That is the old (read 1960's) way, and does not tell you how much draw, but rather that the test light works.

Any current draw tests should be done with a digital multi-meter (less than $30 at radio shack). A digital multi-meter will show you how much draw there is.

Unlike a test light, which only shows you that there is a light bulb.

See, all cars have some draw from computers, clocks, radio back up, etc. For the FC it is typically 40-70 mA (milliamperes). Enough to dimmly light that old test light.

So putting a test light in there is just about as useless as turning on the headlights to test current draw.

Now if there was a current draw problem...say a light bulb or relay stuck on from a bad switch (or relay) that adds about 50mA more current draw... so if you had originally a 50mA draw and add another 50mA, could you tell the difference in light bulb brightness on a typical 5 watt test light bulb??? No way in heck you could. In fact to even double the brightness of a 5 watt test light bulb you would need to have a 2.3 Amp draw.

But with a digital multi-meter, you could see that 50mA difference as bright as day.

Test lights only have one purpose... to poke hole in things, not ever to test electronics in any car made after 1982.

 

If the unit is shutting down and there are charging problems, you may need a cap for the amps. You can toast the alt. with too much amp draw and the battery will not hold a charge. The groung strap is a step in the right direction. You can by a battery/Charging system tester from Harbor Freight for about $40. It may save you time and money from the autoshop diagnostic charge.