Front Power Transistor Test

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

Remove the passenger's dashboard undercover (see PASSENGER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ).
Disconnect the 4P connector from the front power transistor.
Measure the resistance between terminals No. 3 and No. 4 of the front power transistor. It should be about 1.5 kΩ.
- If the resistance is within the specifications, go to step 4.
- If the resistance is not within the specifications, replace the front power transistor.
NOTE: Also check the front blower motor. Front power transistor failure can be caused by a defective front blower motor.

Fig 1: Measuring Resistance Between Front Power Transistor Connector Terminals No. 3 And No. 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Carefully release the lock tab on terminal No. 1 (RED) (A) in the 4P connector, then remove the terminal and insulate it from body ground.

Fig 2: Locating Lock Tab On Terminal No. 1 (RED) In 4P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Reconnect the 4P connector to the front power transistor.
Make sure the RED wire is completely isolated, then supply 12 V to the No. 1 cavity with a jumper wire.
Turn the ignition switch to ON (II), and check that the front blower motor runs.

If the front blower motor does not run, replace the front power transistor.
NOTE: A faulty front blower motor can cause the front power transistor to fail. Before replacing the front power transistor, check the front blower motor for binding, and replace it if necessary.
If the front blower motor runs, the front power transistor is OK.