No rear air 2019 Traverse

[Sonders]

I posted this over on Traverseforum, but thought I'd try here as well.  The rear air isn't blowing on our 2019 Traverse.  The fan speed and mode can be changed on the rear hvac controls in 2nd row, but the rear blower fan never kicks on to blow air through the vents.  I removed and tested the blower fan and it does work.  I then tried jumper wires from the blower motor resistor wiring, directly to the blower motor and again, the blower kicks on and blows cold air through the vents.  I thought this meant the resistor was bad so I replaced it with a new one, which still didn't work.  I also tried swapping out the 30 amp fuse for the rear blower which didn't make any difference either.  Any ideas on what else to check?  I saw mention of replacing the HVAC control panel on another thread on Traverseforum, but not sure if they meant the main control panel in dash up front, or the panel in 2nd row for rear controls.  Thanks in advance for any assistance.

[newdude]

44 minutes ago, Sonders said:

I posted this over on Traverseforum, but thought I'd try here as well.  The rear air isn't blowing on our 2019 Traverse.  The fan speed and mode can be changed on the rear hvac controls in 2nd row, but the rear blower fan never kicks on to blow air through the vents.  I removed and tested the blower fan and it does work.  I then tried jumper wires from the blower motor resistor wiring, directly to the blower motor and again, the blower kicks on and blows cold air through the vents.  I thought this meant the resistor was bad so I replaced it with a new one, which still didn't work.  I also tried swapping out the 30 amp fuse for the rear blower which didn't make any difference either.  Any ideas on what else to check?  I saw mention of replacing the HVAC control panel on another thread on Traverseforum, but not sure if they meant the main control panel in dash up front, or the panel in 2nd row for rear controls.  Thanks in advance for any assistance.

 

 

Seeing you have functioning 2nd row controls, I assume that in the CLIMATE app on the radio screen that you can control the rear fine from there?  Just no fan.  

 

Do you have any codes or have you scanned for codes?  Need a reader that can scan vehicle wide not just ECM/TCM P codes or airbag and ABS.  GM dealers have a SAVI they can scan the whole car, on the cheaper side BlueDriver can scan vehicle wide as can Topdon.  Topdon also has bi-directional abilities.

 

IMO, sounds like you've got something going on either with the main HVAC control module, or the power to the auxiliary blower control module (aka the "resistor" you already replaced).  Do you have 12v or higher at the plug to the motor?  Should be the gray wire with brown stripe is the 12v to the motor.  

Edited August 15, 2025 by newdude

[Sonders]

Just tried controlling the rear air from dash controls and that doesn’t work either.  Also I failed to mention in my first post but the rear controls only change the air flow from ceiling to floor, but fan speed didn’t change when I had the jumper wires on the blower motor; it blows full speed regardless of changing the fan speed on the rear controls.  I’ll have to check the voltage at plug like you mentioned Newdude.  I’ve only tried the jumper wires so far.