Only getting heat from ventilation system
May 30th, 2019, 1:06 PM
#1
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Only getting heat from ventilation system
Hi,
I have a 2005 Uplander and noticed an issue now that it is hot out. If I move the dial to cold and turn on the fan, the air blowing out is very hot, similar to when the heaters are on and the dial is on hot. Prior to the problem, when the dial was on cold, it would blow cool air even if the AC was not engaged.
I tried putting the AC on and it still blows hot. The compressor of the AC will engage for a moment, then turn off....re-engage for a moment then turn off and continue. However, the air is always blowing hot.
My first guess is that maybe the freon leaked and therefore no AC, however, the air should still be somewhat cool when it is set to cold without the AC on. The truck did have to be boosted this winter after a few failed starts,and I am wondering if that had anything to do with it? I also read that a blend resistor can cause this issue....is that correct? I have never worked with a blend resistor and don't even know where it is located on the car. All fuses were checked - truck currently has 95,000km.
Any ideas on what else I should be checking? My gut thinks this may be an electrical problem given the reputation for terrible electronics.
Thanks!
I have a 2005 Uplander and noticed an issue now that it is hot out. If I move the dial to cold and turn on the fan, the air blowing out is very hot, similar to when the heaters are on and the dial is on hot. Prior to the problem, when the dial was on cold, it would blow cool air even if the AC was not engaged.
I tried putting the AC on and it still blows hot. The compressor of the AC will engage for a moment, then turn off....re-engage for a moment then turn off and continue. However, the air is always blowing hot.
My first guess is that maybe the freon leaked and therefore no AC, however, the air should still be somewhat cool when it is set to cold without the AC on. The truck did have to be boosted this winter after a few failed starts,and I am wondering if that had anything to do with it? I also read that a blend resistor can cause this issue....is that correct? I have never worked with a blend resistor and don't even know where it is located on the car. All fuses were checked - truck currently has 95,000km.
Any ideas on what else I should be checking? My gut thinks this may be an electrical problem given the reputation for terrible electronics.
Thanks!
May 30th, 2019, 3:11 PM
#2
There is a door who's job it is to blend air coming from the heater and the chiller. Yours is probably stuck on hot. You are right, the door is driven by an electric motor. Unfortunately, the door can be buried quite deep inside the dash, but if you're lucky you might be able to access the connections by taking off a few kick panels (I am not familiar with Uplanders).
You can try moving the door manually to find out if it's a mechanical issue. You can try applying 0 - 12V to the actuator motor to make sure that's working. If it's OK then you know the problem is the wiring harness or control panel. The dial on the controls should be producing a variable voltage.
BBB Industries- Premium Alternators, Starters, Power Steering Products and Turbochargers | TSB and Wiring Diagrams Database
You can try moving the door manually to find out if it's a mechanical issue. You can try applying 0 - 12V to the actuator motor to make sure that's working. If it's OK then you know the problem is the wiring harness or control panel. The dial on the controls should be producing a variable voltage.
BBB Industries- Premium Alternators, Starters, Power Steering Products and Turbochargers | TSB and Wiring Diagrams Database