Blower Power Transistor Test

NOTE: LHD type is shown, RHD type is symmetrical.

1.Remove the passenger's dashboard under cover.

2.Disconnect the 4P connector from the power transistor.

3.Measure the resistance between the No. 3 and No. 4 terminals of the power transistor. It should be about 1.5 kW.

  • If the resistance is within the specifications, go to 4.
  • If the resistance is not within the specifications, replace the power transistor.


4.Carefully release the lock tab on the No. 1 terminal (BLU/YEL) (A) in the 4P connector, then remove the terminal and insulate it from body ground.


5.Reconnect the 4P connector to the power transistor.

6.Make sure the BLU/YEL wire is completely isolated, then supply 12 volts to the No. 1 cavity with a jumper wire.

7.Turn the ignition switch ON (II), and check that the blower motor runs.

  • If the blower motor does not run, replace the power transistor.
  • If the blower motor runs, the power transistor is OK.