Air Conditioning Question
Thread Starter
|
Freshman User
Joined: Feb 2008
Posts: 40
Likes: 0
Air Conditioning Question
I have a 2006 f350 with the 6.0 diesel and the fan for the heat/air conditioning started acting weird. It now is either off or wide open. There is no in between. It is the electronic controled air conditioning. I was wondering if anyone else has had this problem and knows how I can fix it. As in my area there are no real trust worthy dealers with good mechanics so I would like to try to fix it myself. Thanks for any help you can give me.
Postmaster
Joined: Jun 2008
Posts: 2,564
Likes: 11
From: Wayyy NoCal, USA
Unfortunately, I do not have specific knowledge of the f350 with the electronic controls... However, to get you started:
1) Get your hands on a schematic. It will show you if your truck has what I'm about to describe.
2) MOST vehicles share a common design for fan motor control - a resistor "pack". This is basically a module with 3 or 4 high current resistors. When in off position, no current flowing. When in low speed, fan motor wire is directed through a relatively high resistance resisitor. Medium speed will be through a relatively low resistance resistor. High speed will bypass the resistors entirely.
As you can see, if the resistor pack has an internal open, only off and high speed will work.
Resistor pack failures are not terribly uncommon as when the current is flowing through the various resistors, they generate a lot of heat. The thermal cycling stresses connections, so they may fail over time.
Most of the time, the resistor pack is mounted through the wall of HVAC plenum after the fan so air is blowing over it (and keeping it somewhat cooler) when in use.
1) Get your hands on a schematic. It will show you if your truck has what I'm about to describe.
2) MOST vehicles share a common design for fan motor control - a resistor "pack". This is basically a module with 3 or 4 high current resistors. When in off position, no current flowing. When in low speed, fan motor wire is directed through a relatively high resistance resisitor. Medium speed will be through a relatively low resistance resistor. High speed will bypass the resistors entirely.
As you can see, if the resistor pack has an internal open, only off and high speed will work.
Resistor pack failures are not terribly uncommon as when the current is flowing through the various resistors, they generate a lot of heat. The thermal cycling stresses connections, so they may fail over time.
Most of the time, the resistor pack is mounted through the wall of HVAC plenum after the fan so air is blowing over it (and keeping it somewhat cooler) when in use.
