Q: How to troubleshoot and fix issues with the HVAC system and Blower Motor on Chevrolet Blazer,S10,GMC Jimmy and Sonoma?
A: To troubleshoot and fix issues with the HVAC system, start by checking the fuse labeled HVAC and inspecting all connections for looseness and corrosion. Ensure that the battery is fully charged. With the transmission in Park and the parking brake securely set, turn the ignition switch to the Run position without starting the vehicle. Locate the blower motor, which is housed with the air conditioning Evaporator on the right side of the firewall in the engine compartment. Back probe the blower motor electrical connector using two small paper clips and connect a voltmeter to the connector and ground. Move the blower switch through each position and note the voltage readings, as changes in voltage indicate varying motor speeds. If there is voltage present but the blower motor does not operate, it is likely faulty. Disconnect the blower motor connector and connect one side to a chassis ground and the other to a fused source of battery voltage. If the blower still doesn't operate, it is faulty. If there was no voltage present at the blower motor at one or more speeds, and the motor itself tested OK, check the blower motor resistor. Back probe the connector to the resistor while it is connected and look for varying voltages at each speed switch position. Disconnect the electrical connector from the blower motor resistor and with the ignition on, check for voltage at each terminal in the connector as the blower speed switch is moved. If the voltmeter responds correctly, the resistor is likely faulty. If there is no voltage present from the switch, then the switch, control panel, or related wiring may be faulty. To change the resistor, remove the three mounting screws and pull it from the housing.
Q: How do you remove the blower and fan from a heater housing on Chevrolet Blazer,S10,GMC Jimmy and Sonoma?
A: To remove the blower, start by removing the two mounting screws. Disconnect the blower motor cooling tube and carefully pull the blower up and out. To install, attach the fan to the motor and then insert the blower motor back into place, and fasten it with the mounting screws. Reattach the upper housing panel using the three mounting clips and ensure that the cut edges are aligned properly.