Why do you think that?
That circuit is standard, and using the FQP27P06 should work well, but I would lower the gate resistor to 1K or less.
Switching to a depletion-mode P-channel MOSFET allows the circuit to achieve “Normally Closed” when the Arduino is off or if the controller fails. This is a safety feature of the circuit to ensure the headlight will continue to operate whether the controller is functioning or not.
In the circuit posted, the MOSFET is normally OFF (open) until the npn transistor is switched ON. Is that what you want? Also, your resistor arrangement is no good.
No, it needs to be Normally ON until the NPN is switched on. This is why I was thinking a depletion-mode transistor. Unless there is another way to design this circuit so common stocked parts are used.
For ‘normally on’ you need a third drive transistor, or a mosfet driver chip with a ‘normally low’ output.
That circuit is dangerous, because a power spike >25volt will kill the gate of that mosfet.
A zener (~18volt) across source/gate is needed for automotive applications.
1.2mA gate pull up (10k) is rather low (switching losses/heat). Make it 1k.
Hope you are not trying to dim halogen lights. They have a shorter lifespan dimmed.
Thank you everyone for the 1k Gate recommendation. Adding the zener in serial with the 1k gate pull up should protect against an power spikes while switching, correct?