Caution: If your car stereo has an anti-theft setup, keep its activation code with you before you disconnect your battery. The blower unit sits inside the cooling assembly under the dashboard and below the passenger seat, depending on whether the car has a rear heating system. Examine the fuse and all connections in the blower electrical pathway for worn out or broken contacts. Make sure the battery is fully charged. Locate the blower unit electrical connector. Turn the ignition key On, keep the engine off, and check the blower motor connection. Remove its electrical connector, then switch on the blower speed control knob and measure battery voltage at the blower motor. Low voltage at the blower indicates a bad ignition feed circuit, a damaged blower switch, break in the main relay, or a broken connection between the blower switch and the motor. When battery voltage is present, join the terminal to the blower motor, and check the correct wire for power by grounding it with a short electrical connection. The motor must be broken because it continues to not work. Connect grounded power and ground to the terminals on the blower. If it runs now, get a new motor. When the motor works correctly but doesn't run, test the blower resistor for electrical connections between its input and output terminals. You need to take out the bracket holding the blower connector for removal, then unscrew and take down the blower assembly from its housing. Because you can take the fan away, add it back to the new motor. First disconnect the motor from the blower unit, then make sure it works correctly.