Hi all,

Would like to intro myself a lil first, im Jun, from Malaysia. Please excuse my english, is not my 1st language.

I'm driving a Subaru JDM STi Ver8 here. I have been having this voltage problem for months now and is driving me nuts.

 

Im going to try to put as simple as possible. My car voltage has been dipping below 12v whenever im coming to a full stop. Doesn't matter with day or night driving. WIth full load (A/C, headlights and stereo on) makes it worst, it could go down to around 11v. With just A/C and stereo on during daytime, it will dip to around 11.8-12.v. Whenever i drive, cruising, i could only get about 13-13.3v max.

Here is what i have done so far:

-Battery Changed

-Alternator checked. Swap and try few other alternator from my other subaru friend's and is still the same. Even tried a Legacy alternator (some say the legacy alt has higher amp)

-Pulled a direct cable from battery positive terminal to the alternator

-Additional grounding and even throw in a Pivot Voltage Stabilizer

-Checked all the fuses

-Unhook my audio system, doesn't make much difference at all ( im running very minimal audio setup, 2 amps, single 12", front components)

Everything i did above, still doesn't my car voltage.

I had this same problem before last year around September, it was before i put in additional grounding. After i put in the additional grounding the problem solve. And it come back again this time, i tried put in more grounding (just a try) doesn't work anything.

This low voltage effected my DCCD system, last year when i had this voltage problem, my DCCD green light was blinking indicating something is wrong with the DCCD system. This time my DCCD is blinking as well. I am pretty sure it has to do with the voltage problem i am having.

Now i have come to a halt, not sure where to troubleshoot or fix anymore, is there something i miss? Something i haven't look into yet?

 

thank you for reading hey, really appreciate if someone could help me out..

 

Have you changed any of the pulleys that spin the alternator?

some cars won't charge if the "battery/charging" light is burned out on the dash

oh yes, i forgot to mention, i was using lighten under-pulley at first but i swap back to stock crank and alternator pulley now. Still doesn't work.

Big J: Hi J, what do you mean burned out on the dash?

sometimes the low voltage waring bulb is actually part of the circuit.

hi J,

I dont think mine has a low voltage warning bulb anywhere. How i detected the problem initially was just looking at my Apexi pen turbo timer that showing the voltage.

I thought the turbo timer is in-correct, i tested voltage again with multimeter, it does show the volt is really low.