Electrical problem on '86 GMC S15

I was driving my truck last night when the lights began to dim to nothing. Continued driving home, and vehicle ran fine, but no electrical (no radio, interior lights, exterior lights, etc.). When got home, battery was completely dead. So my conclusion is that it is probably the alternator (battery was replaced a month ago) but can your car still run with a dead alternator? I thought that the fuel pump would still need juice? Any ideas?

Thanks,

Matt

P.S. Haven't had a chance to check the voltages at the battery when running, etc. Will be doing that tonight.

Reply to
Matt Doyle
Loading thread data ...

Yes, the car can run without the alternator, until the battery dies. The fuel pump,computer, etc will run off the battery for a little while. How long depends upon the age and condition of the battery. The battery light should have come on when the alternator failed, but I have had two personal vehicles fail this way. The regulator controls the light, and that was the defective part. Your regulator is in the alternator.

Reply to
CURLY

Hi Matt,

It sounds more like a wiring problem than an alternator problem. If you didn't have enough voltage for dash lights then your spark and fuel pump should of been long gone. Check your fusible links and ground connections. Good luck.

Reply to
jediwrench

Won't be the alternator (at least, not only the alternator), since that wouldn't cause your radio and lights to die. I'd guess there's a bad connection somewhere, like maybe a fusible link..

Reply to
Robert Hancock

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.