Vehicle: 2003 Toyota Sequoia, 2WD, V8-4.7L (2UZ-FE)
Problem: The vehicle came in to the shop because the HVAC blower was not working. The technician found that the A/C compressor and blower motor were both inoperative. This vehicle was equipped with an Automatic HVAC system.
Details: The technician said that he could apply power to the blower motor resistor and the blower motor would run. Next, he checked for circuit power and found that the 10A heater fuse in Instrument panel fuse box was blown. He replaced the fuse but the blower motor still did not work. Looking at the wiring diagram he realized that there should be power on two wires at the blower motor relay socket. There was only one wire with power.
He removed the under-hood relay box to check the connectors and found that the fuse/relay box had corrosion on the connectors.
Confirmed Repair: He cleaned the connectors and reinstalled the fuse box and rechecked the operation of the HVAC system. The blower motor and A/C compressor were working normally.