Forced air fan (heating/cooling) runs only in hi-speed position. on 2001 Dodge Ram Van 3500

Noticed issue recently.Both front and rear fans (heating/cooling)behave the same

It'd be unusual to have this problem in both heating systems at one time, but it sure sounds like faulty blower resistors or switches to me.
An auto electric shop or a Dodge specialist may be able to help you.
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