air conditioning problem on 2004 Toyota 4Runner

My drivers side air is blowing hot and only the passenger side is cold. I don't have dual air. I spoke with a shop who said I may have a dual air box with a door that is not working properly. They said they would have to remove the glove box and dismantle the air system to fix the door or the motor that drives the door open and closed. Does this sound right? Is this something my husband (who is mechanically inclined) could do himseld and if so is there a manual online available? Thanks for your help.

Asked by for the 2004 Toyota 4Runner
This is Toyota's tech info system available to the dealers. "Regular" people can buy a brief subscription to look up service information for their vehicle but it is not what I would consider "cheap"... $15 per 2 days or 75/month
AllData is a very good resource and another information source used by professionals nationwide. It's 26.95 per year and has lots of diagnostic information.

Many Toyota specific message boards, or boards specific to the Tacoma/4Runner have DIY how-to threads, which can be very helpful with pictures taken by users.

Often in the case of heating and AC, mode door arms and/or actuators can fail. This will likely require some electrical knowledge in order to diagnose the failure point if the door or arm isn't obviously broken. Many of those individual parts are available from the dealer and most cases won't require the complete replacement of the HVAC housing.

By the way, if the housing needs to be completely removed, it is best to let a shop equipped with AC refrigerant tools to remove the housing because the AC Evaporator core contains the pressurized refrigerant.

hope this gives you something to go on!