I have been reading up on ways to increase the voltage of the alternator output. A diode is used commonly on trucks and GM vehicles for car audio performance.

The purpose of this is to maintain much better battery charge during times where the ecu thinks its only giving 12.3 volts for fuel economy.

I have noticed on my 20Ah SVR audio battery, that it cranks a bit longer after slow moderate drives, but barely hesitates to start if its been after a hard drive.

The battery is fine, it still starts the car after even a week of sitting (like when I was messing with my exhaust woes)

A DIODE has approx. a 0.5 volt drop across itself. you insert this diode on the voltage sensing wire of the alternator. The result is the alternator does not see 14.4 volts where it should be while charging. it sees 13.9 volts. as a result, the alternator adds 0.5 volts to the charging voltage.



AMPERAGE IS NOT INCREASED!! This is voltage only.


Biggest improvements besides obvious starting power will be stronger power accessory operation, and should clean up performance of stereo!

WARNING: installing the diode backwards will cause damage! the alternator wont see any voltage, and will go nuts trying to make it happen.

So fellow Fit owners, I am looking for a proper alternator pinout. The online manuals do not list it, and the diagram that usually accompanies all import alternators is not in my line of site.

If any of you have recently replaced their alternator, kindly look on the old one for the pinout diagram

Thank you