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Truck Repair/blower fans


QUESTION: international 9400 1995 model the blower fans have quit working no power to the motors have replaced resistors both relays and the control switch checked the breakers also but  no success there is power at the resistors and it changes when you change the controls from low medium and high but no power at the motors have checked grounds on the motors also and they seem to have a good connection the fans will run if i take a jumper from resistors to the fans but the resistors get extremely hot there is 2 wires that go into the harness to the dash that do not have power is there another relay i have missed or ???

ANSWER: there should be a fuse for the blowers one in the bunk and one in the your front fuse box. Those should be good though if your getting power to the switch. those 2 wires were they hooked to the fans or not hooked up if they were not hooked up to anything probably a optional accessory the truck doesnt have. I would start checking wiring between switch and fan all that dash wiring is just laying in there umost sharp edges of dash components could have rubbed through. Might be easier to use a ohm meter and ohm out the wire from the switch end to the fan end.

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QUESTION: will do the ohm check.The wires that feed the motors must go back to switch after the resistors so i really need to get a wiring diagram to know what the wire numbers are I tried to jump strait from the resistors to the motors but only can get low and med unless i jump to a differt post on resistor and can get high  it acts like there is something that takes feed from the resistors to control the speeds which should be (the switch) although i put a new one in maybe a faulty new one but it and my old act exactly the same thanks for replying

ill do some digging and see if i can find you a wiring diagram probably will be this evening before i can get you something if im able.
Did a little research before work have you checked all your plugs alot of people have said that the 9400 when the resistors go bad they burn the plugs which makes them lose contact.  

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Jeff Drumm


I Can answer any question pertaining to semi trucks and trailers. Have no experience in the automotive field so not able to help in that area.


My experiences in Semi Trucks is. I own my own truck and i presntly maintain a 80 truck fleet. Can handle any questions pertaining to a truck have tore apart and rebuilt every aspect on them. Fleet I deal with is Mainly Volvo trucks and a handful of freightliners. Work on automated transmissions on a daily basis along with carrier apu's. With engines my specialty is the 60 series Detroit but do work on the cummins isx the n-14 and the ism. and also the Volvo engines.

Have a College Degree from university of northwestern ohio in diesel and agriculture mechanics. Have 10 years behind the wheel driving a truck and 4 years working on trucks full time. Also have grown up on a farm so have been tinkering on trucks and tractors all my life.

Awards and Honors
I've gone through online schooling and have received certificates from webb wheel, Timken and Volvo academy.

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