Blend door actuator
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
This is the blend door actuator for the C60, manual HVAC system: Item Details
The actuator can only be installed one way, and the door will automatically be in the correct position. DO NOT operate the actuator without installing it. If you do, the actuator will overtravel and destroy itself. On the manual HVAC system, (C60) the calibration procedure is not necessary, it's plug & play.
The actuator can only be installed one way, and the door will automatically be in the correct position. DO NOT operate the actuator without installing it. If you do, the actuator will overtravel and destroy itself. On the manual HVAC system, (C60) the calibration procedure is not necessary, it's plug & play.
I have a 96 Jimmy with manual climate control. I now only have hot air with temp selector in all positions. Everything else works as it should. Could this be a blend actuator problem? If so, how do I access it on a 96 Jimmy?
New Member
Joined: Jul 2013
Posts: 9
if after you figure out which blend door actuator you need to replace manual or auto, you may end up with a very common problem were the blend door is cycling and unable to find it's limits. This problem has driven me crazy for six months since i changed the battery out. All the threads here and on most other sites give the basic calibration procedure. this says to remove the dro bat fuse for 20 seconds, with the power off, then put it back and turn the key to the on position for 40 secs. all good except it is missing a very key step.
I have finnally nailed the problem down thru an honest Chevy mechanic. "this is a known problem throughout many of the chevy product lines. in order to fix it the five volt signal needs to be jumped to one of the pins on the connector to the unit can first find it center positon. The aforementioned cal procedure can only find the limits but without the center position being first calibrated the DRO bat fuse removal procedure cannot work". This is exactly what i see happening. Chevy does have procedure for calibrating the unit about $100.00. but not to fret. there is a tsb 150-9645 that explains which pins to jump. I will post it as soon as i can. i did the procedure last night and it work!
Of course this is a real design issue that chevy will not take responsibility for and therefore they expect the owner to pay a 100.00 fee. Change a battery and then pay $100.00 to have heat and air conditioning again.
go figure.
I have finnally nailed the problem down thru an honest Chevy mechanic. "this is a known problem throughout many of the chevy product lines. in order to fix it the five volt signal needs to be jumped to one of the pins on the connector to the unit can first find it center positon. The aforementioned cal procedure can only find the limits but without the center position being first calibrated the DRO bat fuse removal procedure cannot work". This is exactly what i see happening. Chevy does have procedure for calibrating the unit about $100.00. but not to fret. there is a tsb 150-9645 that explains which pins to jump. I will post it as soon as i can. i did the procedure last night and it work!
Of course this is a real design issue that chevy will not take responsibility for and therefore they expect the owner to pay a 100.00 fee. Change a battery and then pay $100.00 to have heat and air conditioning again.
go figure.
BF Guru
Joined: Dec 2016
Posts: 5,609
From: Moscow, ID
Looks like I'm not the only one with an HVAC air temp issue. Mine is only delivering hot air through my Automatic HVAC system.
Any luck with the TSB?
Christine
Any luck with the TSB?
Christine
Super Member
Joined: Oct 2008
Posts: 1,786
From: Tucson, Arizona
cudaguy71 and christine_208: since this thread is about three years old, doubt that the TSB was ever posted here, might try doing a Google search for it.
Are you both having hot air out the vents with AC on? Assuming the AC system is functional, easy thing to do is to watch the blend door actuator movement with the temp setting at full hot, then full cold...or the other way....just to see if it is moving then we can go from there.
Are you both having hot air out the vents with AC on? Assuming the AC system is functional, easy thing to do is to watch the blend door actuator movement with the temp setting at full hot, then full cold...or the other way....just to see if it is moving then we can go from there.
New Member
Joined: Jul 2013
Posts: 9
cudaguy71 and christine_208: since this thread is about three years old, doubt that the TSB was ever posted here, might try doing a Google search for it.
Are you both having hot air out the vents with AC on? Assuming the AC system is functional, easy thing to do is to watch the blend door actuator movement with the temp setting at full hot, then full cold...or the other way....just to see if it is moving then we can go from there.
Are you both having hot air out the vents with AC on? Assuming the AC system is functional, easy thing to do is to watch the blend door actuator movement with the temp setting at full hot, then full cold...or the other way....just to see if it is moving then we can go from there.
BF Guru
Joined: Dec 2016
Posts: 5,609
From: Moscow, ID
theorizing...
I just looked at mine again, I could hear the blend door actuator motor running with the key in the RUN position but motor off. What I did not hear is anything that sounded like a door moving back and forth.
I recently had to put a new battery in my Blazer but I cannot be sure if the actuator went bad at the same time. However, looking at online videos I can see how it could only take one bad (i.e. hard to move) situation for the key gear to crack. Perhaps the motion associated with the re-initializing of the actuator after losing power puts extra strain on an already weakened gear, hence the correlation between disconnecting the battery and these actuators going bad.
Christine
I recently had to put a new battery in my Blazer but I cannot be sure if the actuator went bad at the same time. However, looking at online videos I can see how it could only take one bad (i.e. hard to move) situation for the key gear to crack. Perhaps the motion associated with the re-initializing of the actuator after losing power puts extra strain on an already weakened gear, hence the correlation between disconnecting the battery and these actuators going bad.
Christine