1993 Buick LeSabre:
My voltage meter has dropped below normal and the dummy light continues to stay on. I have replaced the battery and also installed a NEW alternator. No change in the faulty electrical. I have no cold air blowing on me (the fan still works) turn signals are sluggish and the cruise control does not work. What do i do? What is wrong? It is hot in AZ now and I am dying for some AC and i love my cruise control for my long commutes too. I use trickle charger on my bnattery every night because my commute drains the battery from 10-12 down to 8 or below by the time I get home from work. During the day i start my car twice, once to leave home and then again to leave work.
It sure sounds like the alternator is not charging the battery when the engine is running. Have a mechanic measure the battery voltage with the engine running. It should be between 13.5 and 14.5 volts DC. If it truely is in the range of 10-12 volts, then have him check the voltage on the B+ lead of the alternator. If that is substantially higher i.e. 0.5 volts or more, have him check the continuity of the B+ lead from the alternator post to the positive terminal of the battery. There may be an open fuse or blown fuseable link.
The fact that the charge idiot light is lit indicates that the alternator is not building voltage. BTW is the charge idiot light as bright with the engine running as it is when the ignition switch is in the run position and engine ‘off’? Since the idiot light lights that means that starting field current is getting to the regulator but why the alternator is not producing is the question. The mechanic should investigate that. You might have a bad NEW alternator so have the alternator checked free of the car.
Get back to us with additional information because this is a tough dog that has the hallmarks of a learning lesson.
Good advice from Researcher. As he stated, check for a bad fuse or fusible link that connects the alternator output to the battery. Hopefully you will find the trouble there. Check the connections on the alternator also and make sure they are making good connection.
One thing that may also be happening that wasn’t mentioned is the lead field lead coming from the warning light may be shorted to ground somehow. That would turn on the light but disable the alternator. To see if that is the case you could remove the plug on the back side of the alternator and the warning light should go out, if the wiring is ok. If it stays on there is a problem.
With most charging systems, the wires to the plug on the back side of the alternator should have voltage close to the battery voltage present on the wires when the ignition is ON.