2006 Escalade: A/C unresponsive and wont turn off

[Morten]

Hello,

My dad has a 2006 Escalade where the climate system seem to have a life of its own.
It runs on full blast regardless of if you turn the fan speed up/down, it also stays on after turning the car off, and it is only blowing hot air regardless of what you set the temperature to.

After googling around I found people saying its the PCM thats fried, however I am not able to find any PCM part number, does anyone what the part number is for the PCM?

does it sound likely to be the PCM or am I looking in the wrong place?

Any help would be appreciated, thank you in advance.

 

[Morten]

By the way; if I pull the fuse for the blower motor, then the fan switches off.....so I am pretty confident that its the PCM or whatever control module controls the climate system

 

[Fless]

The fan speed is likely independent of the hot air issue, but they could be related if the HVAC module is having issues.

More likely, though, for the fan speed is the blower motor resistor. Easy enough to get to and test:

The hot air issue is likely an HVAC temp actuator issue.

 

[Morten]

The fan speed is likely independent of the hot air issue, but they could be related if the HVAC module is having issues.

More likely, though, for the fan speed is the blower motor resistor. Easy enough to get to and test:

The hot air issue is likely an HVAC temp actuator issue.

I think its unlikely to be the resistor causing the issues my dad is experiencing. But I'll test the resistor like he is describing in the video tomorrow just to eliminate that.

Thank you your input and for sharing the video.

 

[Morten]

Apologies for the late update, its been snowing like crazy here.

I just removed the resistor from my dads escalade, and it looks completely different than the one he shows in that video. The one my dads truck has only has a 3 pin / terminal connector and the the 7 pin / terminal one he shows in that video

 

[Morten]

I think the part number on it is 9643

 

[Morten]

 

[Morten]

 

[Morten]

 

[Morten]

Corrosion is always a good sign....

 

[Morten]

Correction, after googling around the part number is 4P1516

"AC blower motor resistor Module 4P1516"

 

[Morten]

I made a video trying to see if there’s any continuity in the resistor.

There is on the positive from the battery, but nothing on the input or ground.

Is this normal?

(Sorry English isn’t my first language)

 

[Morten]

Testing for ohms on the ground and input pins.

I got a reading on the ground pin but nothing on the “input” pin.

Again; I have no idea if this is correct or not, but thought I’d mention it anyway.

 

[Fless]

I don't see anything that details how to test the original part, but I didn't look all that hard. And it looks like the replacements are not like the originals and will require a slight change in wiring, with instructions typically included with the new part.

For the updated part, you can go here: https://wvebrand.com/part-details/4P1516/#content

Click on EXPAND ALL
Scroll to the bottom where there are instructional documents

Or this seems to have the original style connections:

Amazon.com

 

[Doubeleive]

I made a video trying to see if there’s any continuity in the resistor.

There is on the positive from the battery, but nothing on the input or ground.

Is this normal?

(Sorry English isn’t my first language)

it's probably bad, that is the only thing that will allow the fan blower to continue to run when the vehicle is shut off.
i would replace it and that will fix the "fan always on problem"
the heat only problem is "most likely" a actuator, but could be other things like mentioned before such as the ac temp control unit

 

[rockola1971]

Yup, its the automatic blower control module. If you look at the schematic you will see that it is made to default to high setting for blower if the resistor part of the module fails. This is in case you are driving in a temp range that could cause ice or fog to buildup on windshield. Its GM's way of saving those that would try to drive around with no defrost if the module failed.