Mode Control Motor Test

NOTE: Check for HVAC DTCs.

1.Disconnect the 7P connector from the mode control motor.



Incorrectly applying power and ground to the mode control motor will damage it. Follow the instructions carefully.


2.Connect battery power to the No. 1 terminal of the mode control motor, and ground the No. 2 terminal; the mode control motor should run smoothly, and stop at Vent. If it doesn't, reverse the connections; the mode control motor should run smoothly, and stop at Defrost. When the mode control motor stops running, disconnect battery power immediately.

 

3.If the mode control motor did not run in 2, remove it, then check the mode control linkage and doors for smooth movement.

  • If the linkage and doors move smoothly, replace the mode control motor.
  • If the linkage or doors stick or bind, repair them as needed.
  • If the mode control motor runs smoothly, go to 4.

4.Use a digital multimeter with an output of 1 mA or less at the 20 kW range. With the mode control motor running as in 2, check for continuity between the No. 3, 4, 5 and 6 terminals and the No. 7 terminal individually. There should be continuity for a moment at each terminal as the motor moves past the switch's terminal.

5.If there is no continuity for a moment at each terminal, replace the mode control motor.