How can I check my A/C Heat Climate Control switch?

Hi,

First, I attached the wiring schematic below for the system. This is for manual climate control. If you have something different, let me know.

First, check fuse 12 in the fuse junction box. If it is good, confirm there is power to and from it. Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If the fuse is good and there is power, go to the blend door actuator connector and locate the pink wire with a dark green tracer. Confirm it has power at the actuator with the key on.

If it does, go to the heater control unit (on the dash) and locate the dark blue wire with a red tracer. It should have 12v as well. The control unit provides a ground path. So, check for a black wire near the passenger side airbag (be careful working around the airbag). Locate the violet wire with a white tracer in the connector at the control unit and check for continuity to ground. If there is none, repair the ground. Note: The violet/white wire splices into the black ground wire. (See schematic).

If there is continuity to ground and you have power at the control unit, there is a chance the control unit has failed.

Let me know what you find or if you have other questions.

Take care,

Joe

See pics below. Note: I had to cut the schematic in half to make it readable. I did overlap them so you can follow from one to the next.

Happy to help. Let me know the results. I'm interested in knowing.

Take care,

Joe

Hi,

Good job checking. At this point, either the controller is bad, or the blue/red wire is open. When you checked that wire for power, did you do it at the actuator or the control module?

If at the actuator, disconnect it and check right at the pin or back probe the blue/red wire right at the module to see if it is providing power.

Let me know the results.

Hi,

The dark green/pink supplies power directly to the controller. Power can also be introduced via the blue/red wire in the opposite direction to turn the actuator motor in the opposite direction.

So based on your description, it works one way but not the other. Are you getting power at the pink/dark green wire at the actuator? Power is supplied to that wire via the same fuse dark green/pink wire but through a different wire to the actuator.

If you are not getting power to the pink/dark green wire, that is why it won't go the opposite direction.

Let me know

Joe

See pic.

Okay, then either there is no power out from the actuator to the controller, the ground is bad, or the controller is bad.

If I recall, you checked the ground. Also, when you tested for power at the blue/red wire out from the actuator, did you provide your own ground? If you did and there was no power, it sounds like the problem is at the connector on the actuator. The controller provides a ground path for that wire to complete the circuit. Providing a knowing good ground and testing at the actuator, you should see power. So, inspect the wiring very closely and the connector as well.

Now, if you provide a knowing good ground and there is power, the controller is the likely cause.

Joe

You are very welcome. Just make sure power stops at the controller and there isn't a wiring issue. I don't want you to spend the money if it is something different.

Take care and let me know how things turn out.

Joe

Hi,

Thanks for the update. I'm glad you got it working.

Please feel free to come back anytime in the future if you have questions.

Take care,

Joe