I tapped into the power leads going to the tire pressure monitor/homelink transmitter (black module in front of ceiling lights) to power my Valentine 1 radar detector. Soon after I connected the wires, my tire pressure light came on which made me think I bungled something up. I referred to the manual which said it would turn on the light if the pressure dropped 25%. I checked the pressure in all four tires and found they were all 30 psi - a little low but not 25% low. I checked my wiring again and found no problems.

So, I inflated the tires back to 34 psi and the light went out - nice. Since the temps here in TN have dropped about 20 degrees in the past three weeks, I figure this is enough to drop the tire pressure a couple psi. I'm happy to know the tire pressure monitors are that sensitive and work well.