My tranny light comes on when I start the rig I also have a dead alternator, could this be causing the light to come on?
Tranny light + bad alt.
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at temp light
The two are linked together. When my alt went south, the AT oil temp on my 62 also came on. Replacing the bad alternator should be all you need to do.
The two are linked together. When my alt went south, the AT oil temp on my 62 also came on. Replacing the bad alternator should be all you need to do.
If the voltage regulator on the solenoid went bad would that set off the AT light too? I assume the alternator would not work without a funtioning voltage regulator? Just curious.
Wile E Coyote
Out in the streets, they call it murder!
My understanding is, the alt 'full fields' when the VR takes a dump. Full field=full voltage, like 14.8v and higher (usually higher, like 16v)
So why would we want a VR on our alternator? What is wrong with going without one and always putting out full voltage? Bad for the battery? Bad because of heat in the windings would cause excessive heat and wreck the alternator? Just trying to learn more about the system...
Wile E Coyote
Out in the streets, they call it murder!
While a nominal 12v system is actually optimized around 14.2v ideally, it get's pissy at the higher voltages I mentioned earlier. Electrical devices are of course designed with certain parameters, (resistance being the prime factor in this example) and with higher voltages comes higher resistance ( assuming same circuit, same devices) One example would be filaments in light bulbs. The filament in my example is sensitive to the increased resistance, thus the VR is there to deliver a safer voltage. One of the signs that a VR may have taken a sudden dump, is the brightest headlights ya ever seen on your rig. Trouble is, they potentially burn out within minutes.
There is an upper limit for what a battery will take in Voltage w/out going bad, and potentially even exploding. I don't remember exactly, but it's ~15.5 V. High 14's are safe, 15 is borderline, more than that and you're looking for trouble. Also, remember that most guages have an error, so while it might show a V of 15.4 (and thus "OK") the actual V to the battery might be 15.6...
Long story short, a properly functioning VR is a good thing to have.
