I hate verbal descriptions of circuits... it always sounds more complicated than it actually is...
Consider the attached schematic. The Lamp is driven by the PIC. Pin goes High, Lamp goes ON. A single ULN2004 can drive 7 Lamps. There are driver chips that can can do eight. Doesn't have to be a chip, you can use Transistors, but you need Base Resistors and all kinds of junk, and since the ULN can drive an inductive load (such as a Relay) you don't need Diode back-emf surpression as it's built-in.
Just two components needed. A Resistor and a Zener. Those two parts will prevent the PIC pin from having 12v applied back to it. This example uses two PIC pins, one to drive the Lamp, the other receives a HIGH if the Lamp is Good, and a LOW if the Lamp is Blown.
You can combine both on one PIC pin, but the circuitry would more components. As you have it now you just have one Resistor and one Zener per Lamp.
Actually, as an afterthought, you'll need a second Resistor across the Zener (say 47K) to ensure the pin is Pulled-DOWN when the Lamp blows, otherwise it's technically floating.
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