My climate control system on my 06' F250 has a mind of it's own. I can't turn it off(goes to defrost blower when switched to off) and I don't have control over the fan speed(I get indication via the display that the fan speed changes, however its on high speed always). Any ideas? less than 10K miles on this one(just).

Thanks,

Jim

 

Sounds like a vacuum leak.

Is your truck a 4x4? Does your truck have ESOF?

 

Yes, 4 X 4 ESOF.

 

Is your ESOF working properly?

 

"Is my ESOF working?"

Good question, I will try it.

Jim

 

I checked the ESOF and it works. The symptom of defrost on high when hvac is off along with no fan control(always on high) is intermittent. 1 time in 10, it will work correctly.


Jim

 

Well, the symptoms have changed. Now the HVAC can be turned off, but when on, high speed fan is the only setting that works. Any of the lower settings, do not.

Thanks,

Jim

 

In the dealership this morning. I will let you know what they find.


Jim

 

Probably the vacuum solenoid for the ESOF will be replaced.

 

Sounds like a bad EATC head unit. Could also be a pinched vacuum line in the dash or a bad vacuum pump. There is a TSB out on these.

 

Well, after having the truck overnight(waiting for HVAC controller), the dealer ship called on Friday and said they have to order a high speed blower. I questioned the guy saying the High Speed fan works great, it's the other speeds that don't. He then says it needs a relay right next to the High Speed fan. Anyway, they put it back together and said come back next week.

Jim

 

I know some of the Chryslers have a resistor bank next to the blower motor that controls the fan speeds. Our van lost all speeds except high, and the resistor bank was bad. It only cost $12 and took 5 minutes for me to swap it. Perhaps Ford has built theirs into the blower assembly and requires replacing the entire motor.

 

All is well. Final culprits were the HVAC control module and the Blower control module.


Jim

 

I saw your post from a while back and was wondering if you could explain what was the fix? Was it 2 items replaced? Or did they replace the blower control mod but it was actually the head unit?

I have the same thing a/c works on high and when you turn off the a/c the derfrost blows on high.

Thanks

 

They replaced the HVAC control unit first which did not fix the issue. They then changed the blower control module which did indeed fix the issue.


Jim