jmgratz
Original Owners Club Member
Maybe one of you Ford mechanics can answer this question. I am trying to hook up an air compressor to the 15 amp (switch 4) to the upfitter switch in my 2010 F350. The owners manual says there are blunt cut wires under the dash on the left side of the steering column. I did find the bundle of wires there and about 15 blunt cut wires. According to the owners manual the brown wire is supposed to control the 15 amp circuit which is switch 4. So when switch 4 is on I should get 12 volts to the brown wire if the ignition is on. Well I get 4.5 volts to the brown wire and the upfitter switch has no affect on it. The 4.5 volts goes to 0 when the ignition is turned off. All of the other wires have no voltage except for the green with yellow tracer which has 12 volts all the time. I need a switchable 12 volts and thought the upfitter switch would be the way to go. Can someone tell me whats up. I checked the fuses and found the upfitter fuses and they are okay and give me a constant 12 volts.