Frustrating day for the 99 F150.

Just when I thought it was a heater blend door, I ordered a " heater treater" model and just completed taking everything apart down to the heater blend door actuator. The spline on top of the actuator wasnt turning, so I assumed that the actuator was bad rather than the blend door.

So, I replaced the actuator and the new one doesnt move the spline either. So, I think it could be that two actuators are bad- doubtful, or the problem is in the rheostat ( hot to cold ****). It's been less than a year since I replaced that part too.

Is there something that I am missing in my troubleshooting analysis?

thx

jay

 

I just replaced the actuator motor this past weekend.....mine didnt move either.....i tool the spline out of the old one and stuck it up in the blend door and moved it by hand....you could just tell that the door was fine.....i was getting no heat......ended up being my water pump....but the actuator motor was bad also.....

 

My 99 f150 had the same problem, removed the glove box, cut into the heater box for the heater treater way and my blend door is fine no cracks. Bought a new blend door motor and still doesn't move, my question what should i remove to get to the heat & cold dial, that has to be the problem...has anyone replaced one? Thanks.....i have pictures if NEEDED

 

There is possibly a problem in your controller unit. The mechanism is directly behind the inst. panel. If possible get a controller from the dealer, and make a substitution.

The pot's in that unit fail after so many years of use.
BTW the controller ip unit is the panel that you use to turn on/off/ control the hvac on your truck.

 

Any luck?

 

i just replaced the temp control in the panel and still no heat either.i have replaced the thermostat and both heater hoses are getting hot. but only cold air blowing out. any idea's?? the blend door is fine i guess. it switches from vent to floor and defrost. just cant get warm air

 

You're talking about your mode doors, (vent, floor, defrost) the blend door determines how much hot and how much cold comes thru. Two different animals.