QuestionQUESTION: Hello, I'm having a problem with either my battery, my alternator, or maybe a fuse. I have a 1991 Toyota MR2. There is a fuse in my fuse box called (ALT 102) do you have any idea what that's for? Could it be for the alternator? My car feels like it starts at only 50% I just bought a brand new battery with connections, the alternator is about a year old and I'm not sure what's making it start and run only 50%. Do you have any idea? And do you have any idea if it could be the broken fuse?
ANSWER: Tha tfuse not only supplies power to the altwernator but just about every other electrical system on the car, if it was blown the car would never start and there would be no dash lights or running lights and no accessories would work, the problem is not the fuse, if the engine does not crank over and there is a clicking noise while trying to start it the starter is problably going out, if the engine does turn over but not fire up there could be a lot of other possible causes so let me know if that is the case.
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QUESTION: Hello, I don't believe it's the starter because my car starts fine, sometimes it just seems as if the battery is dying as I'm driving. The ALT fuse blew out awhile back and I had to buy a new one, although....the connection that the fuse plugs into is all messed up from blowing, so I kind of had to jam in the new fuse. Do you suppose the new fuse is only fitting into the connection %50, which would make the alternator work %50? Which it would keep the battery charged only %50, which the car would only operate %50? I also know it's not the alternator because it's only a year old. Let me know what you think. I also wanted to mention that the fuse we are talking about doesn't fit %100 into its slot, it sticks up a little bit. If you think this is the problem, do you know how I could fix it? Thank you so much!
ANSWER: Do you mean the 120a alternator fuse or the 7.5 a fuse, there are two alternator fuses, to me it does sound like the battery is being drained while driving and mot being charged by the alternator so whatever is going on with the fuse is probably the causes, it could have an intermittent open condition.
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QUESTION: I'm talking about the 120a alternator fuse, sorry for the confusion. Does this fuse control the alternator and electrical connections? What do you mean an "intermittent open condition"? Do you have any idea how to fix that other then bringing it to a dealership? I really appreciate your help!
AnswerThat fuse supplies power to the alternator, the large white wire on the single post on the alternator, the fuse also prives battery voltage to almost every other circuit in the car except the starter. If the fuse is not installed securely there may be an intermittent open circuit which means the flow of current may be interrupted because of vibration from the vehicle, this is why the fuse is bolted in.
