Blend door actuator does not respond to hot/cold knob

[LeakySeals]

It would appear the 2013 Equinox has 2, maybe 3 different Climate control options. Mine has no auto button on the panel. No sensors in the vent box. I don’t see much else controlling the actuators other than the climate control panel. I can turn the blend door manually and get heat or AC. So I know I have the right actuator and there is nothing wrong with the heat or AC. I just can’t change it from the panel turning the knob. Looking online there are multiple climate control/radio panels with different part numbers, each look a little different. Not a cheap part to replace.

I took the old blend door actuator apart. Check out this pic. What type of 12v switch or knob would I use to bypass the climate control panel and adjust the motor of the actuator? Looks like a B10k-L5 marking on the small circuitboard, assume that’s a pot code.

 

[Dave9]

What (where was) this green PCB, was it behind the console knob, or on the back of the motor?

If it's a potentiometer, probably 10K ohms but you can measure resistance with multimeter, "probably" between the two outer legs on it. Similarly you can measure whether it is working by measuring resistance between either outer leg, and the inner leg, that it registers and changes as you rotate the pot wiper with the center hole turning.

If it was behind the console knob, where does it go next?

It would help if you could dig up some wiring diagrams.

 

[LeakySeals]

What (where was) this green PCB, was it behind the console knob, or on the back of the motor?

If it's a potentiometer, probably 10K ohms but you can measure resistance with multimeter, "probably" between the two outer legs on it. Similarly you can measure whether it is working by measuring resistance between either outer leg, and the inner leg, that it registers and changes as you rotate the pot wiper with the center hole turning.

If it was behind the console knob, where does it go next?

It would help if you could dig up some wiring diagrams.

This is what it looks like assembled. The board is internal to the actuator.

 

[eljefino]

The problem is it is a stepper motor, and there is software that limits its travel. If you just put 12 volts to it you would break things trying to get "more heat" or "more AC."

You'd need to reinvent the wheel to control it with something like an Arduino.

The most logical redneck fix is to fit something like a manual choke cable to the actual flapper in the airbox.

 

[Dave9]

^ I don't think it is a stepper motor, looks like only two wires to it and the pot attached by the gears, tells the controller the position.

 

[LeakySeals]

The problem is it is a stepper motor, and there is software that limits its travel. If you just put 12 volts to it you would break things trying to get "more heat" or "more AC."

You'd need to reinvent the wheel to control it with something like an Arduino.

The most logical redneck fix is to fit something like a manual choke cable to the actual flapper in the airbox.

Which was exactly the problem with my 06 Escalade. The module for the rear heat/AC was defective. It would overdrive the blend door actuators and get them stuck. Pushing a manual button or switch I won’t know when I’m about to hit the the case with the door. So.. redneck fix it is. Fortunately, the blend door is accessible behind the glove box, and the glove box is not held in by anything.

 

[Dave9]

This is what it looks like assembled. The board is internal to the actuator.

What I posted previously applies. You can measure for the resistance, and change in resistance between either outer leg of the pot, and the middle leg when the gears turn. It could be that they don't make use of the full travel of the pot, but it should still continue incrementing in resistance in the kΩ range.

If it seems to work correctly then the problem is upstream of it.

 

[eljefino]

What I posted previously applies. You can measure for the resistance, and change in resistance between either outer leg of the pot, and the middle leg when the gears turn. It could be that they don't make use of the full travel of the pot, but it should still continue incrementing in resistance in the kΩ range.

If it seems to work correctly then the problem is upstream of it.

But then the computer "recalibrates" itself by carefully moving the motor until the current draw increases, which tells it that it's stalled at the end stop. So then the potentiometer only tells it it's getting to its last known position.

By the time you re-engineer all this logic you might as well put in a manual whatever and do it by feel!

 

[Dave9]

^ Current? I am doubtful. Seems like what it should be doing is current limiting, to not destroy the gears or plastic blend door, then when it senses no further change in resistance value from the pot, that it is then in the fully open, or fully closed position.

 

[spackard]

For my ‘92 Acura Vigor I rebuilt my mode control motor assembly a couple of months ago and my recirculation motor assembly a couple of weeks ago. The assemblies are a few hundred each; the Chinese motors are maybe 3 for $16. (MABUCHI RF-370CB-11670)

The OP’s motor sounds functional. Cleaning the sensor sounds like a good guess. But then I read he doesn’t think his HVAC box has one.

I think the black thing with the white half-moon shaft senses where the blend door is, and likely is a passive potentiometer, feeding the resistance back to a controller.

 

[mrbreezeet1]

The problem is it is a stepper motor, and there is software that limits its travel. If you just put 12 volts to it you would break things trying to get "more heat" or "more AC."

You'd need to reinvent the wheel to control it with something like an Arduino.

The most logical redneck fix is to fit something like a manual choke cable to the actual flapper in the airbox.

Yeah, akin to back when things were simple!
@ Leaky seals, Maybe a wiring diagram would help you?

 

[mrbreezeet1]

Yeah, akin to back when things were simple!
@ Leaky seals, Maybe a wiring diagram would help you?

So.. redneck fix it is.

Never mind.

 

[jws555]

One more comment. This thread has discussed the actuator and switch as possible defective items. What about the wire harness?
No corrosion on the pins, no bent or missing pins, no broken or frayed wires, firmly seated, all at both ends?

Regards,
John

 

[mrbreezeet1]

You'd need to reinvent the wheel to control it with something like an Arduino

I had this $h(t box car one time, I don't remember what the bad component was, but I thought of hooking up a $10.00
Arduino board and a pot on the dash for the blower motor speed control.

 

[mrbreezeet1]

One more comment. This thread has discussed the actuator and switch as possible defective items. What about the wire harness?
No corrosion on the pins, no bent or missing pins, no broken or frayed wires, firmly seated, all at both ends?

Regards,
John

Good thought! But wouldn't the fact that the previous owner and leaky seals unplugged the actuator, and the blend door went to the opposite extreme rule that out, or am I missing something?

 

[LeakySeals]

Redneck blend door actuator V1.0. When it gets colder, I’ll tighten it up.

 

[Dave9]

^ Absolutely but since he has the pot exposed, it can be ruled out

I had this $h(t box car one time, I don't remember what the bad component was, but I thought of hooking up a $10.00
Arduino board and a pot on the dash for the blower motor speed control.

Why would you need the arduino board? No need for one or the power supply for it, to drive a simple brushed DC motor (if that's what the blower motor is, as most are).

You could use a mosfet on a heatsink plus a pot, or build or buy something PWM, example:

20A PWM DC Motor Speed Controller 12V 24V 36V 48V /w Potentiometer Knob Switch | eBay

Find many great new & used options and get the best deals for 20A PWM DC Motor Speed Controller 12V 24V 36V 48V /w Potentiometer Knob Switch at the best online prices at eBay! Free shipping for many products!

www.ebay.com

It might need a little tweaking of the resistance the pot produces, to get good linearity of full pot travel vs motor speed. There's also the option of getting whatever automotive automatic climate control motor speed controller that will fit in the airstream duct to the blower for cooling, and reverse engineer it enough to see if it needs anything more than just a potentiometer for control.

 

[mrbreezeet1]

^ Absolutely but since he has the pot exposed, it can be ruled out

Why would you need the arduino board? No need for one or the power supply for it, to drive a simple brushed DC motor (if that's what the blower motor is, as most are).

You could use a mosfet on a heatsink plus a pot, or build or buy something PWM, example:

20A PWM DC Motor Speed Controller 12V 24V 36V 48V /w Potentiometer Knob Switch | eBay

Find many great new & used options and get the best deals for 20A PWM DC Motor Speed Controller 12V 24V 36V 48V /w Potentiometer Knob Switch at the best online prices at eBay! Free shipping for many products!

www.ebay.com

It might need a little tweaking of the resistance the pot produces, to get good linearity of full pot travel vs motor speed. There's also the option of getting whatever automotive automatic climate control motor speed controller that will fit in the airstream duct to the blower for cooling, and reverse engineer it enough to see if it needs anything more than just a potentiometer for control.

Yeah, something like what you linked to. I'd have to see if I can find it on Epay, but I had in mind the same board and pot that I used for my metal lathe to drive my threading/longitude lead screw off of an ~ 12V power supply and a junkyard wiper motor Via a V belt.

 

[mrbreezeet1]

Yeah, something like what you linked to. I'd have to see if I can find it on Epay, but I had in mind the same board and pot that I used for my metal lathe to drive my threading/longitude lead screw off of an ~ 12V power supply and a junkyard wiper motor Via a V belt.

Yeppers! That looks like the one I used TBH!
I can't go back that far to when I got the little board, but that looks like it.
I used a different pot and wired a different power switch and a DPDT reversing switch in it too!

 

[jws555]

Redneck blend door actuator V1.0. When it gets colder, I’ll tighten it up.

Maybe velcro in V2.0?

Regards,
John