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[gdanaher]

This problem troubles me because I haven't figured out why the light stays on. Does the intensity of the light change between the engine being off and the engine running? Unless things have changed, the principle is this: The wire runs through the positive side of the battery via the ignition switch to the alternator. An alternator just doesn't create electricity like a generator. It sorta needs to be primed like a water pump if you think of that way. That wire provides that little bit of 12 volts to do the job and it flows from the battery to the alternator and in so doing, the light glows. When the alternator stats charging, it balances the voltage and the light goes out. A diode in the alternator prevents voltage from flowing backwards to the battery, thus preventing high amperage from flowing through a small wire. I have seen a dim glow after starting and this was the fault of a failed diode. For the light to stay on with multiple alternators means that obviously something else has failed, but what? All I can think of here is that the wire is touching ground somewhere between the bulb on the dash and the alternator, so look for that. The wire must still be connected to the alternator for it to work. Look for a frayed insulation on that wire toughing ground. If nothing else, jiggle the wire around and see if the light goes out. Good luck, and report back, because this one bugs me.

One more thing. If you have access to another vehicle do this--turn the key on so that the alternator idiot light comes on. Under the hood, pull or other wise disconnect the small wire going into the alternator. Letting it hang lose in space, check back for the idiot light. It should now be out. Do the same to your Camry. If the light is still on, then the wire is grounded and you just need to figure out where. Any chance some rats came to visit the car while it was parked? They like to play games like this. Look for damage to the wiring harness holding this wire.