Do you mean they simply don't work when installed, I hope? There really isn't anything in the vehicle that can destroy a generator, and by their very nature, they are self-regulating as far as current is concerned. They simply will not produce significantly more current than they are designed for.
First, does the battery light turn on as soon as you turn on the ignition switch? If so, that circuit is ok. It is the "turn-on" signal for the voltage regulator. You should also find around 2.0 volts on the green wire in the regulator plug when the light is on. Once the system is working, there will be near full battery voltage on that wire and that voltage will turn the light off.
Next, there must be full battery voltage on the yellow wire all the time. That is the main power source for the regulator and it is the wire the regulator uses to sense system voltage. If that voltage is missing, look for a blown 15 amp fuse.
There must also be full battery voltage on that fat black / orange wire all the time. If that one is missing, look for a blown very large bolted-in fuse. It could have been blown by the previous generator but more likely that wire touched ground and arced, especially if you didn't disconnect the battery while doing the replacement.
You won't find any voltage on the white wire at first, but when the generator is working, there will be near half of full battery voltage on that wire. It's that voltage that tells the regulator to raise the voltage on the green wire to turn the light off.
There are two ways to tell if the system is working. Look for around 6 volts on the white wire, or measure battery voltage while the engine is running. The voltage must be between 13.75 and 14.75 volts. Besides identifying a no-charge condition, the regulator will also turn the warning light on in the event of an over-charge condition.
Sunday, November 7th, 2010 AT 9:49 PM