If i had the alternator fail through failed diodes , would i see very large sparks when trying to connect a battery? The narrative here suggests i would: http://www.thefierofactory.com/qabatrundown.php Thanks Ian V6 ferrari 308 replica fiero, battery was dead, now replaced but fusible link popped at c500 connection
[This message has been edited by Drfiero308 (edited 12-23-2013).]
Originally posted by Drfiero308: Hi everyone If i had the alternator fail through failed diodes , would i see very large sparks when trying to connect a battery? The narrative here suggests i would: http://www.thefierofactory.com/qabatrundown.php Thanks Ian V6 ferrari 308 replica fiero, battery was dead, now replaced but fusible link popped at c500 connection
You will most likely see a spark when ever connecting the battery cables,regardless if your haveing any problems.If you have a charge gauge on your dash,it would probubley be reading way low,or way high (over or under chargeing), another symptom would be static comeing over the radio speaker. More detailed information on your problem would help. I asume your battery isnt charging and there could be other causes. Worn headlight motors can easily drain the battery (try disconnecting the single power wire to the right and left headlight motor). Battery acid,on your battery cables,can prevent the battery from charging. A stuck fan relay can drain the battery too (doesnt happen very often,but the relay can stick).
[This message has been edited by James Bond 007 (edited 12-23-2013).]
Thanks for reply. I have another thread on forum detailing a broader set of issues but summary is as follows " I bought a nice fiero 308GTB replica last week. It had a dead battery but jump started fine. The battery clearly was dead as a new one was required and simply connected the new battery in parallel to allow me to drive the car home (which it did fine for about 250 miles). Cabin volt gauge indicated between 12 and 14 volts - needle periodically flickered between these two displayed values. I changed the battery over the weekend - which is a bit of a fiddle given the poor access. Car fired up fine but volt gauge showed 10v or so and, when driving around clearly was falling gradually. A multimeter across the battery terminals indicated no charge being received from the alternator. In a fiero, the positive battery point has a feed to a nearby connector block, from which the main red cable links to the alternator. There is a fusible link in this cabling. I poked around this connector block area and noted that a PO had cut the fusible wiring in the alternator cabling and then crudely wound the wires together and covered it in tape for some reason. I thought my poking around might have disturbed this connection and that this would explain why i had no charge to the battery. I reconnected this with a short 27amp length of cable and then reattached the battery. Immediately, there were lots of sparks and the newly installed spliced cable simply melted. Clearly I had a short that was earthing the battery directly through this cabling.
Reading around the topic as I can tell, then I could have failed diodes in the alternator allowing a direct connection to earth? But just a bit confused as to why this happened now when before the battery install, even with the dodgy connection i found, the car was charging and running reasonably OK? Just a coincidence of problems?
Car is a 1987 Fiero V6 with aftermarket 308GTB body fitted. The dash alternator light had never come on at any time" Thanks
That is a sensing circuit for the regulator in the alternator, so if there is any resistance, the circuit will do it's job. In theory, you could put the wrong bulb in, or the filament could break in a way that completes the circuit, and it would still work, but the light would be off. It looks as though your luck has run out, though, and the circuit is now open.