My left alternator light came on. I am assuming that means the one alternator has failed or will soon fail. Car starts no problem. When I turn on the A/C and the lights, the alt gauge dips very slightly below center. Normal driving the needle is slightly to the right of center. Optima battery. Question, I want to take the the car to an event this weekend about 50 miles away. When I return, it will begin to get dark. Lights. I can avoid using A/C at night. Anyone have this experience, and will I be OK driving for about 100 miles depending on just one alternator without stopping?
Ron - with judicious use of electrical loads you should be okay. When the radiator cooling fans come on, along with the fuel pumps and A/C, lights, wipers, etc., a single alternator will not suffice. However, on a cool evening at highway speed, you radiator fans will stay quiet. The single alternator will provide sufficient output for CD ignition and lights. Even if the fans come on intermittently, the battery reserve will provide ample current, and will catch up its charge when the fans go off. I would not worry, but be conscious of what electrical devices you turn on. Jim S.
I would not drive it until you get the alternators rebuilt. Weak alternators caused my BB512i to start running hotter than normal a few years back as the battery alone did not have enough current to run the fans at full speed.
Good point. Thanks. Just to check, I let the car warm up, the fans came on no problem, both temps were normal, the amp gauge also stayed normal. Going any distance still concerns me. Is it possible that this warning light is also for something else?
A few years back I noticed my BB512i started running about 100c rather than the 90c it had been running every since I had the car...all three fans were spinning when the A/C was on, so we checked everything else, thermostat, temp sensor, radiator itself all to no avail. ..at the advice of a friend I carried my car to AutoZone for one of those free alternators test hookups...as it turned out my alternators were putting out about 1/2 the current they were supposed to...while the fans were spinning, they were not spinning at full rpm to keep the radiator cool...after I had both alternators rebuilt at a cost of about $150 each, my water temp went back down to 90c were it still runs...you can now fly a kite over the front radiator vents in my Boxer...
