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Mode Door Actuator

ss502gmc

By ss502gmc
in Ask A GM Technician

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ss502gmc Enthusiast

ss502gmc

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Posted

Hi, I have posted about this before but I recently fixed my mode door actuator in my 01 2500hd and its the one under the dash on the drivers side that controls the defrost, dash, and floor vents. I didnt think it was necessary to replace since it started working again after manually turning it back to the middle "probably a bad thing but i was irritated" so here me out. I noticed that when operating it in my hand turning the control knob that if i turned it all the way to defrost it would get stuck there but after installing it worked fine so i put everything back together and it worked fine till now and it is now stuck on defrost again. Any input would be awsome and also is there an easier way of working on that thing besides ripping apart the whole dash? Thanks guys!!!

ss502gmc Enthusiast

ss502gmc

Posted
  • Author
Posted
Hi, I have posted about this before but I recently fixed my mode door actuator in my 01 2500hd and its the one under the dash on the drivers side that controls the defrost, dash, and floor vents. I didnt think it was necessary to replace since it started working again after manually turning it back to the middle "probably a bad thing but i was irritated" so here me out. I noticed that when operating it in my hand turning the control knob that if i turned it all the way to defrost it would get stuck there but after installing it worked fine so i put everything back together and it worked fine till now and it is now stuck on defrost again. Any input would be awsome and also is there an easier way of working on that thing besides ripping apart the whole dash? Thanks guys!!!

 

 

No input?

233monte Enthusiast

233monte

Posted
Posted

No there is no easy way to workon that. Most doors in there have foam around the outside to seal. A lot of times the foam comes off. That could be why it hangs up.

Norseman Senior Enthusiast

Norseman

Posted
Posted
No there is no easy way to workon that. Most doors in there have foam around the outside to seal. A lot of times the foam comes off. That could be why it hangs up.

 

Yup, you are correct it is the foam that makes it stick. The foam gets tacky as it ages. Scrape it off, that is what I did to mine and that did the job.

ss502gmc Enthusiast

ss502gmc

Posted
  • Author
Posted
No there is no easy way to workon that. Most doors in there have foam around the outside to seal. A lot of times the foam comes off. That could be why it hangs up.

 

Yup, you are correct it is the foam that makes it stick. The foam gets tacky as it ages. Scrape it off, that is what I did to mine and that did the job.

 

Thanks i will try that, but the funny thing is is that when i was holding the actuator in my hand "not attached to the hvac box" it stuck a few times in the same position. its like it bottomed out or something. it would not do it at all if i didnt turn it all the way to defrost. Do you think the actuator may be bad? or the control module? I just dont wanna go through all this multiple times where winters right around the corner and i dont freeze while plowing like last year when this happened.

Norseman Senior Enthusiast

Norseman

Posted
Posted
No there is no easy way to workon that. Most doors in there have foam around the outside to seal. A lot of times the foam comes off. That could be why it hangs up.

 

Yup, you are correct it is the foam that makes it stick. The foam gets tacky as it ages. Scrape it off, that is what I did to mine and that did the job.

 

Thanks i will try that, but the funny thing is is that when i was holding the actuator in my hand "not attached to the hvac box" it stuck a few times in the same position. its like it bottomed out or something. it would not do it at all if i didnt turn it all the way to defrost. Do you think the actuator may be bad? or the control module? I just dont wanna go through all this multiple times where winters right around the corner and i dont freeze while plowing like last year when this happened.

 

 

If you are in there might as well as replace it. If you feel like spending the $$$.

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