2005 Peterbilt 378 C-15

Hello Everyone!! I have a question for the expert people, my fan clutch is not working properly, sometimes engaged and disengage with normal temperature. And in the morning when I start the motor engages and does not let the motor to warm up properly. And it keeps doing that all day engaging and disengaging. I already change the two sensors that deal with fan clutch and the solenoid and still doing the same thing. Does anyone has a clue what the problem might be? Thank you all for your answers.

 

No, a/c is off defrost off.

 

Can you please tell me where that high pressure switch is located?

 

Thank you very much for your help! I will check it and hope will be it.