no blower in second ( rear) seat headliner

[Stilllearning6]

1997 Suburban - rear seat overhead roof liner control knob / blower unit does not turn on the fan . The third seat blower does get juiced , so I suspect a simple switching connection , or the blower .

Question - after the rectangular plastic bezel is removed from the roofliner control knob area, how do you access the blower switch and /or the blower for troubleshooting ? Any schematics available ?

I tugged and twisted and turned the frame / mounting plate w/o being able to remove it . Are there secret screws ? secret latches ? squeeze pressure to release ?

[777stickman]

Actually there is no blower in the headliner. The blower, heater core, a/c and diverter doors are all in the right rear of the Sub. If you're getting air from the lower outlets then the blower is ok. Sounds like a problem with the air diverter door system. My Sub '98 has a front and rear control panel for the rear stuff, does yours and if so do you have the same symptoms from both?

[Stilllearning6]

Thank you for the comments . Here is how I see it --

Everything ( heater , A/C , blower ) in the front seat dash area functions correctly .

Middle /second seat area blower system is not functioning , no forceful air is pushed outward when the middle seat control knob is turned to ON . Note - front dash controls were adjusted / selected to enable middle seat control .

The third seat area blower system functions correctly .

The middle seat area has the control knob for both the "middle / second seat" area and it is this same control knob that also turns on the " third/far rear" seat blower . I can hear/ feel the blower turn on in the third seat area .

There is no apparent air blowing out of the "middle seat / second " seat headliner area when the knob is turned ON . This same knob immediately starts the blower in "third / far rear " seat area .

You indicated that the air flow DIVERTER doorway may not be functioning properly.

Where is this located ? How to access ? Is this controlled by a vacuum hose ? A cable slide lever ?

My only experience in this area has been with cable controlled slide levers all located within the front dash of other model vehicles . In those vehicles , the control cable to swing the vent diverters became disconnected from the control mechanism and the doorways would not slide OPEN / CLOSED .

What is the mechanism here ? Any input is appreciated .

[777stickman]

My Sub is a '98 K2500, but I don't think there is any difference with yours, I hope. The whole rear unit is located behind the interior liner in the right rear, so you have to remove that for access. It's not a real easy thing to do, but it's doable. You'll need to loosen the rear door pillar molding where the right rear seat belt goes through also. If you have any "wrenching" skills at all you'll figure it out. Take your time. When it's opened up you'll see the blower motor at the very rear then the plenum goes forward up and over the wheel well. At the very front end is the "mode door" actuator (air diverter door). It has wires connected to it. This is the door that controlls air flow to the upper outlets or the lower ones or anything in between. If that motor is not working when you operate either the rear overhead or the front overhead controls then it's either the motor or the control module(located behind the rear control panel). I hope this helps you. I got into mine for the rear temp control door..............Steve

[Stilllearning6]

Thank you for the guidance .
Will check out the rear side zone and hope to be able to disassemble for a revealing look .