If a blower motor does not run, where is the best first voltage check location?

• A. At the hot side of the motor terminal
• B. At the switch controlling the motor
• C. At the battery negative terminal
• D. At the ground connection near the motor

Answer: (A)

The most useful first check is to verify the power being delivered to the motor itself. By measuring the voltage at the hot side of the motor terminal, you immediately confirm whether the feed from the control circuit is reaching the motor. If voltage is present there when the switch is on, the issue is not the supply path; the motor or its ground path is the likely fault, and you can focus on the motor windings or the return path. If voltage is missing at the hot terminal, the problem lies upstream—check the switch, relay, fuses, or wiring feeding the motor. Checking the battery negative terminal or a ground near the motor tests the return path, which is important but doesn’t tell you whether the motor is being fed in the first place. Similarly, testing at the switch is useful if you already know the motor isn’t getting power, but the quickest way to determine where the fault lies is to start at the hot side of the motor terminal.