Vehicle: 2006 Chevy Express
3500, V8-6.0L, VIN U, Automatic Transmission
Problem: The customer said the heater and air
conditioning blower does not work.
Details: With the ignition key in the ON
position, the tech verified the HVAC blower motor is not working.
Next, he checked the HVAC blower circuits and found the HVAC
fuses were not getting battery voltage. He applied 12-volt power
to the HVAC fuses controlling the blower and the blower motor
Using the wiring diagram, he traced the power circuit for the
HVAC fuses and found that power came directly from the ignition
switch. He found the ignition switch feed circuit was open in the
Confirmed Repair: The tech replaced the ignition
switch and the HVAC blower ran normally.