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Discussion Starter · #1 ·
First, I had to remove both right rear seat seatbelt anchors on the C&D pillars to take off the pillar trim pieces that overlap the heater panel.

I think there were 5 Phillips screws and a bunch of push-in retainers.... then the whole right rear inner panel came out (somewhat) fairly easily.
..................I did NOT have to remove any seats, etc.

I started the engine to hear the system making that clicking noise again and put my hands on each of the servo-motors to find which was the clicking offender...... easy as there are only two.
..................I could feel the one that clicked and to confirm it, I pulled the electrical connector off - it got quiet.

At this moment I decided to remove the servomotor to see what was going on and if I could fix it - or not. The "or not" part came into view fast.

There are three screws to remove the servomotor and the shaft that it fits on is somewhat of a tight fit - so make sure to pull it up straight! That's important!
  • BTW: the shaft is keyed to the servomotor output gear and will only go on in one position. This is important!
OK --- after taking it out and opening the case up I noticed a broken gear ---the one that mates with the output gear.
...................There were broken gear teeth everywhere.
..............................Bad sign.

I decided that I didn't need rear AC, as I live in Montana and AC isn't REALLY necessary here anyway.
..............The temp never gets over 80F anyway.
.......................Having AC in the front is OK - but in the back is useless.... IMO.

Restarting the engine again, after fiddling with the controlled shaft sticking out of the plenum, I found the position I wanted. The shaft wouldn't stay in the position I wanted when the blower was running.

This called for drastic measures ----> I had to end up putting just the lower gear back into the lower half of the motor case and re-installing the case half with the three screws ---> I just hot glued the gear into the position I wanted. Easy peasy!

No more clicking (a good thing) - no more cold air in the rear (a bonus) - and I can still control the blower and hot temp from the front control and/or the rear controls.

This summer - if we really HAVE a summer this year --- I might investigate into buying a couple of new servomotors just in case.......

In conclusion ----> I suspect that the door(s) that the servomotor(s) control, for some reason don't want to go to both extremes to allow the motors to find the center position.
.....................This seems to be the designed-in system to set ZERO POSITION for the servomotors every time the engine is restarted.

It MAY be collected dirt, a Barbie head or a Lego that won't let it move to one extreme or the other ... I dunnow.

At this time it's still cold here and plastic parts are brittle in the cold - so it will have to be on a warmer day that I go ahead and take the whole rear HVAC plenum assembly apart to ascertain the real reason why the gears are stripped.

HTHs someone...... l8tr
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