Beets125

I just recently installed a 12si gm alternator and had a few questions that i cannot find the answer too. I have a 1982 toyota pickup truck and the original OEM alternator harness wires are colored : green, black, and yellow. (plug is LEF)


- I installed the alternator and used a 4 gauge battery cable with a 175 amp fuse (the alternator is rated at 150 amps).
- Next I plugged in a GM pigtail where the #1 wire was connected to the factory yellow wire (L wire)
- The #2 wire on the pigtail was bolted (jumped) right onto the B terminal of the alternator (same post the 4gauge wire connects from alternator to the battery + )



OEM alternator harness green and black wires were deleted (cut them and tied them off)
OEM alternator battery wire (thick white wire from OEM alt) was cut and tied off (not being used)
External Voltage regulator was removed (unplugged and not used anymore)


I started the truck up and everything is charging fine. Im getting around 14 volts at idle. When i turn on all my lights and accessories im getting anywhere from 12.8 to 13.6 volts. Everything seems to be charging and working fine. My only problem is that my charge light and brake light is staying on. How do i fix this and why is it happening?

SENOR NOODLES

Low brake fluid will charge both lights to come on. I know it does not sound right, but it is.

UTAHYOTA

I wired mine solo. I didn't use the stock harness and simply wired the alternator to the battery and ignition. Then I installed a voltmeter. No problems in 3 1/2 years. The only other thing I did was solder in a diode between the ignition and alternator just as a precaution so I don't accidently fry the ignition.