Is this resistor really needed?

Is the resistor R2 even needed? The NPN is connected to a PIC chip.
If the transistor failed could the 12 volt line get to the PIC?
Thanks

**broken link removed**

Yes, R2 is absolutely essential!

Without R2 the 12v will blow the base-emitter junction of Q2 in milli-seconds.

Without R2 the transistor WILL fail.

JimB

R2 is absolutely needed to limit the current through the base of Q2. The base-emitter junction of a bipolar transistor looks like a forward biased diode, thus the current is limited only by the external resistance if you apply a voltage above the forward bias voltage (about 0.6V) of the junction.

With R2 in the circuit, the 12V will not damage the PIC input, even if Q2 fails.

OK ... thank you!

So principle is (just for the record):