Ok so I paid a visit to my buddies at the local Toyota dealership, Parts Manager, and head-honcho mechanic.
The following is strictly in regards to my Pickup; I am not making any references to any other model. For whatever reason, other's situation may be different.
For my Pickup they said there is no Charge Light/Lamp Relay and it just so happens that this started in my year Pickup, 1988. Prior years did have the Charge Light/Lamp Relay. Just for shifts & giggles, I asked Parts buddy to check 1989 and sure enough there still was no Charge Light/Lamp Relay.
Someone had mentioned a diode, so I asked Parts buddy to check that. The only one that came up was somewhere in the middle of the dash. So armed with all this new info, I went to talk to Mechanic buddy. He said very quickly that it's a bad diode attached directly onto the back of the instrument cluster, and he has dealt with dozens of them and that one had just been in the other day. He said most customers just live with it because the dealership's remedy is they have to replace the instrument cluster/gauge assembly box and that it's too expensive in most customer's eyes. The dealership won't just R&R the diode.
But that doesn't mean I won't try! If I feel like I can de-solder the old one off and solder in something that will work, I'll do it.
Then again I don't need babysitting by some idiot lights. I keep a close eye on my brake-fluid reservoir and I know when my emergency-brake handle is drawn (DUH) so I can do without that brake warning bulb. I can install a voltage meter on/under the dash or with an A-pillar mount and know what's going on with my charging-system so I don't need that bulb either.
And screw you, Toyota, for making customers buy a whole new instrument cluster just because of a little goldang diode!
I just might sell this thing!
