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Power Transistor Test - Rear Heater-A/C

Rear Power Transistor Test

1. Remove the driver's console side trim.
2. Disconnect the 4P connector from the rear power transistor.




3. Measure the resistance between the No. 1 and No. 2 terminals of the rear power transistor, It should be about 1.4 - 1.5 kOhms.
- If the resistance is within the specifications, go to step 4.
- If the resistance is not within the specifications, replace the rear power transistor.




4. Carefully release the lock tab on the No. 4 terminal (WHT/RED) (A) in the 4P connector, then remove the terminal and insulate it from body ground.
5. Reconnect the 4P connector to the rear power transistor.
6. Supply 12 V to the No. 4 cavity with a jumper wire.
7. Turn the ignition switch ON (II), and check that the rear blower motor runs.
- If the rear blower motor does not run, replace the rear power transistor.
- If the rear blower motor runs, the rear power transistor is OK.