Heater Blend Door Actuator

[findog78]

I've been reading through the many many threads on the heater actuator issues. Mine doesn't blow defrost through window vents, it blows hot air randomly through the dash vents with climate control off and its been difficult to pin point which actuator is bad. It seems the one at passenger feet has already been changed by previous owner because the hard to reach screw is missing and I found an actuator in a box under back seat. From what I read there are three and there is lots of different opinions and results. Also opinions about dont buy ACdelco, which part number to buy quality replacement, replace the rear to fix the front two, and on and on. My question is there a sticky or one thread recommended by the salty dogs in hear where someone clearly explains troubleshoot and replacement? Thanks!

 

[Scottydoggs]

have you tried the re calibration yet?

 

[findog78]

Thanks I'll check it out.

 

[Joseph Garcia]

@swathdiver

 

[swathdiver]

I've been reading through the many many threads on the heater actuator issues. Mine doesn't blow defrost through window vents, it blows hot air randomly through the dash vents with climate control off and its been difficult to pin point which actuator is bad. It seems the one at passenger feet has already been changed by previous owner because the hard to reach screw is missing and I found an actuator in a box under back seat. From what I read there are three and there is lots of different opinions and results. Also opinions about dont buy ACdelco, which part number to buy quality replacement, replace the rear to fix the front two, and on and on. My question is there a sticky or one thread recommended by the salty dogs in hear where someone clearly explains troubleshoot and replacement? Thanks!

Well, it's possible that your controller is no good. It is usually a bad actuator. Your issue seems to be the Mode Actuator. A Tech-2 or other bi-directional scan tool that can read BCM codes will know for sure and even tell you why it failed.

GM OE and ACDelco Professional in this case are the same part, both numbers on the same box.

I've been told that this is also for the GMT800s that also have Auto AC.

Double check by plugging your VIN in here:

https://parts-catalog.acdelco.com/acesCat.php?

 

[findog78]

Great info. I'm going to start with this reset procedure and go from there. Thanks.

 

[mattbta]

I've got a Dorman for the Driver's Temp that is about 9 years old -- before I knew they could be bad. When my Passenger Temp needed replacing two summers ago, I went Delco because I didn't want to get back in there again, if a bad part were installed.

 

[findog78]

Well, the youtube reset procedure didn't work. Autozone rents an Innova 3100 CanOBD2 Diagnostic Tool but it doesnt specify BCM codes? Will this work?

https://www.autozone.com/test-scan-and-specialty-tools/code-reader/p/innova-3100-canobd2-diagnostic-tool/987694_0_0

 

[Scottydoggs]

looks like it just a abs scanner.

need a high end scanner like a tech 2 or maybe a snap on scanner will work. why the shops charge so much to scan and diag this type of thing. if they do the repair they drop the diag charge, but if you come in just for a diag they will charge you a hr or two easy.

 

[swathdiver]

Well, the youtube reset procedure didn't work. Autozone rents an Innova 3100 CanOBD2 Diagnostic Tool but it doesnt specify BCM codes? Will this work?

https://www.autozone.com/test-scan-and-specialty-tools/code-reader/p/innova-3100-canobd2-diagnostic-tool/987694_0_0

I've never known those youtube resets to work. Always use a Tech-2 or something like a Snap-On Solus, a bi-directional scan tool.

A Tech-2 will pay for itself after the repair. After that, it'll keep saving you money.

 

[tRidiot]

I did the relearn with a new blend door - no fix. Also looked at the control head next to it (this is rear) and it looks like I replaced that unsuccessfully a few years back - Amazon told me I already bought one. I'm waiting on my Tech2 clone from China to see if I can learn something.

 

[findog78]

Jessup Chevrolet is $189 for diag fee. I'm seeing Tech2 tool for around $240-350 depending on accy's. It's GM specific? Doesn't look like I can use it our Jeep or Nissan? More research! Thanks for replies.

 

[findog78]

I did the relearn with a new blend door - no fix. Also looked at the control head next to it (this is rear) and it looks like I replaced that unsuccessfully a few years back - Amazon told me I already bought one. I'm waiting on my Tech2 clone from China to see if I can learn something.

How much was the clone? I'll be watching to see how it worked.

 

[MassHoe04]

How much was the clone? I'll be watching to see how it worked.

I just ordered a Vetronix Tech2 from chinacardiags.com.
Was on sale for Chinese New Year. Mine was $250 + $72 S&H ($322 total).

Now is $269 + 72 S&H ($341 total).

I didn't see that the one that comes with a hard case offered free shipping, which makes it almost the same as what I paid in the end.

Still great value, I would say. I can't wait to get it! I know I'll get good use out of it. I have a pesky Evap code. I plan to use the Tech2 to verify purge valve, vent valve and solenoids are doing what they should (or not). The Tech2 should help sort out the real cause and save me from playing parts darts game. The Tech2 will likely save much more than what I paid over the next couple of years.

I'll just get a hard case with foam inserts from Harbor Freight. They are about $20-40 depending on what I get.

 

[tRidiot]

Yup, I got the $370 one or so. Ended up about $50 for the case, really.

 

[Scottydoggs]

I've never known those youtube resets to work. Always use a Tech-2 or something like a Snap-On Solus, a bi-directional scan tool.

A Tech-2 will pay for itself after the repair. After that, it'll keep saving you money.

that reset works for my truck. seems every time i take the battery out the heater blend doors fail to work.

 

[MikeW]

Has anyone gone ahead and had their dash removed, heater core changed and all blend doors? I'm at the 20 year point and have similar heat/blowing issues as above. Think may bite the bullet and have them all done at once.....

 

[tRidiot]

My scan tool shipped today - apparently Chinese Spring Break is finally over.

 

[MassHoe04]

My scan tool shipped today - apparently Chinese Spring Break is finally over.

Me too. Mine is due to arrive Wednesday of this week. I am amazed we can get Tech2 scanners shipped from Hong Kong to the US in 1 week, but there are all these "supply chain issues" holding entire industries hostage! As long as I have my Tech2, I'm good!!

 

[Rolexus]

Joining this Blend Door conversation late. Last summer in extreme heat and smoke (forest fires) on trip through Rockies (BC), passenger (lower, by feet) Blend Door quit, and blew HOT air into drivers side, even on AC max cold. Only relief was to turn on defrost to cold, and max cold and fan speed in rear cabin upper vents. YouTube re calibration only worked for short time.

My 05 Tahoe has 4 Blend Door Actuators, all identical: 2 in front dash, 2 in rear cabin.

When got home, replaced this bad Blend Door, then recalibrated - worked til recently (see below).

In Dec, temp dropped below zero. Now rear heat didn’t work - only blew cold air. YouTube again... There are 2 Blend Doors in rear cabin - front one (by rear passenger door) controls air flow (upper vs. lower), other one (mid cabin) controls heat to cool setting. Once at operating temp, played with ceiling console controls, able to determine bad Blend Door was ‘heat to cool’ located mid cabin.

Removed trim, replaced bad one (mid-cabin) with real AC Delco, recalibrated. It WORKED!, and the rear fix also affected air flow throughout, including front (recent clicking noise returned, even though was replaced).

Front cabin replacement from last summer was auto parts store generic, so will be changed again with AC Delco.

TIP: easier to access the passenger side Blend Door (lower) ACCESS which controls drivers side IF remove Center console cup holder... still need to work from passenger foot area, but another hand through the top makes it easier for re and re.

Hope this helps some of you...