2000 GMC 2500 P0102 Fault: Where Does the 12V Power Come From for MAF Sensor?
I'm experiencing a P0102 fault code on my 2000 GMC 2500. The mass air flow (MAF) sensor is showing only 4 volts input, but I expect 12 volts based on the wiring diagram. Where does the 12-volt power supply originate for the MAF sensor? Is this a wiring issue or a faulty sensor?
Refer to bbbind.com for the wiring schematic — the MAF sensor should receive a constant 12V power supply from the vehicle's ignition system. Can you share the MAF reading in grams per second (G/S) from your scan tool? Also, please provide the freeze frame data associated with the P0102 code for better diagnosis.