Rear Air Mix Control Motor 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.

Special Tools Required

Backprobe Set 07SAZ-001000A (2)

NOTE: Before testing, check for HVAC DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).

Disconnect the 7P connector from the rear air mix control motor.
NOTE: Incorrectly applying power and ground to the rear air mix control motor will damage it. Follow the instructions carefully.
Connect battery power to terminal No. 1 of the rear air mix control motor, and ground terminal No. 2; the rear air mix control motor should run, and stop at Max Hot. If it doesn't, reverse the connections; the rear air mix control motor should run, and stop at Max Cool. When the rear air mix control motor stops running, disconnect battery power immediately.

Fig 1: Identifying Rear Air Mix Control Motor Connector Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.
If the rear air mix control motor did not run in step 2, remove it, then check the rear air mix control linkage and door for smooth movement.
- If the linkage and door move smoothly, replace the rear air mix control motor (see REAR AIR MIX CONTROL MOTOR REPLACEMENT ).
- If the linkage or door sticks or binds, repair them as needed.
- If the rear air mix control motor runs smoothly, go to step 4.
Measure the resistance between terminals No. 5 and No. 7. It should be between 4.2 to 7.8 kΩ.
Reconnect the rear air mix control motor 7P connector, then turn the ignition switch to ON (II).
Using the backprobe set, measure the voltage between terminals No. 3 and No. 7.
Max Cool: about 0.5 V

Max Hot: about 4.5 V
If either the resistance or voltage readings are not as specified, replace the rear air mix control motor (see REAR AIR MIX CONTROL MOTOR REPLACEMENT ).