1993 Nissan Sentra alternator or charging system

IKUE32

MEMBER
1993 NISSAN SENTRA
6 CYL
FWD
AUTOMATIC
198,000 MILES

I have recently been having issues with something electrical. I've changed out the battery twice and the alternator several times. The battery and brake light come on together which tends to indicate the alternator. I just had the alternator changed again last Friday and these lights came on last night as I was idling on a hill at a stop light. If I throw it into neutral while I'm slowing down, I won't lose complete power, but if I just stop at a dead stop, everything starts to dim down and sometimes completely shuts down. I don't have any external regualators on the alternator, but I was thinking either the charging system or the voltage regulator, please help. I can't afford to keep dumping money into this, but I can't afford to buy a new car either. I did have one of the guys at work take a meter reading and the voltage was fluxuating, but that was before the last time I changed the alternator.

1 Reply

ZACKMAN

MECHANIC
4,202 POSTS

Your voltage regulator is built-in in the alternator. If you keep replacing alternator because of the lights keep coming on, I would check the wires coming out of the alternator. You have a clip with 3 wires, 1 big wire to the battery, and occasionally a small ground wire. Check all of them, making sure that they are making good contact. Invest in a small voltmeter. With the engine running, check the output on the alternator side, it should read more than 13V. Then check the output on the battery. If it is about 12.6V, then your wiring is to be blamed.