Blower Motor Current Draw Test

Heater Blower Motor Current Draw Test - Schematic:

This in-vehicle test will determine if the blower motor is operating properly.
1. Connect a 0-30 ammeter as shown.
2. Ground the negative side of the blower motor connector with a 10-gauge or larger jumper wire, and measure the motor current draw.
3. If the unit is operating properly, the current draw readings will be within the following Specification.
a. Low 4.5-5.5 amps.
b. Medium Low 7.0-8.0 amps.
c. Medium High 14.0-18.0 amps.
d. High 20.0-25.0 amps.