I have removed both knee bolsters, glove box,etc. All the actuator motors seem to be working all the flaps. Looking up through the right floor outlet vent,I can see the defroster/floor flap move. The recirc motor & flap works. I pulled out the Blower Motor Reistor and Evap Core looks clean,no blockage seen. With Blower on High & Resistor removed, the air escaping through the square resistor hole is tremendous in velocity! The air just is not getting to the outlets. I am second owner, first owner was also faithful at maintanance, including new cabin filter every 10,000 miles. I DON'T want to remove the dash, but I am at a loss to the blockage. Is there a flap closer to the defroster ducts that I am missing? Is there a good HVAC Diagram somwhere? Any ideas?

I know this sounds too simple, but if it was working and then a noise, these units have been know to ingest things, via the motor, which blocks air flow. Son and wife have both had similar problems with plastic bags. Removed the blower and cleaned out the mess and worked again.

Have you removed the motor to check for blockage?

dick

Thanks Dick, that too was my first thought. The first thing I did was pull out the Cabin Filter & look down to the "squirrel cage", no blockage. Second thing was to go inside, pull out the blower motor and look at the box inside, could see to the Evaporator, no blockage. It's just like a flap/door in the box is stuck, yet I can watch the shafts turn when I move the Control Knob. I am going to remove the dash top this weekend and look further. I hate the thought of having to take the Instument panel out as a last resort. I wish I could find a "cut away' picture of the AC/Heater Box. Thanks, Phil

I just sent you an email with an attachment for the 850 heater controls. Near the bottom is a diagram showing the vent damper motor placements, 5 of them. There are 2 next to the driver's side/center console, up where they are hard to reach - of course!

When removing the damper motor, be very careful to make sure the damper and motor do NOT change position. Otherwise, the motor will disable itself, not knowing the limits of open/close positions.

You did not mention if the 2 yellow lights on the recirc/ac switch are flashing when you first turn the car on. The ECC does a "test" of all of its parts at start up and if something is wrong, the lights flash for at least 10 seconds.
This happens to my car when it is too cold and the ECC no longer works correctly. After the cabin warms up, I turn the engine off and restart it, no more flashing lights. Obviously, one of the dampers is slow and needs oil, but which one??? Besides, it is too cold to work on it! A springtime project to lube all of the dampers.

Replacing a motor is quite expensive. Each one costs around $250 at the dealer, and then a Volvo scan tool is required to "reprogram" the ECC unit to set the new damper motor.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Thank You very much, Klaus, for your reply. I had downloaded that info from the VolvoSpeed site, thanks to 'Made in Japan' (I think he should be 'Made In Sweden' as he is a wealth of information, like yourself). I studied it and cannot determine what could be blocking the airflow. I wish there was a good 'cutaway' picture of the ac/heater box so I could follow the path of air leaving the blower motor/fan. There must be 1 flap & actuator that I cannot see up high in box. I have determined 4 actuators/flaps, L & R Temp, Floor and Recirc, are working.
No, there are no flashing lights at startup or anytime. My wife said she heard a noise under the dash and then there was almost no airflow at any setting. There is plenty of heat, just very little circulation, even with blower on high.
Thanks again and let me know if you have any new thoughts, Phil

From what you say, it appears that the floor/defroster damper is stuck in the floor mode. Behind the motor, the vane that turns the damper may have broken. This can be glued and wired back together. Just be very careful that you know the current location of the vent - try to have the dials in the dash set to floor before removing the motor. Do not run the motor if it is not attached to the vent damper.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

I thought the floor/defroster damper was the lowest one, I can see up from the right side floor outlet, and see the flap open & close. Maybe I am seeing the ventilation damper. Is the defrost/floor damper higher up in the box? And can I access it with the dash in? Thank You for your rsponses Klaus.

Damn IRS and taxes.

There are 2 vent motors against the center console, as viewed from the pass footwell. Upper left is the pass side temp damper. Down and center is the floor defrost damper. The F/D damper is a pain to get to, I took mine off in my 850 and took forever to get it back on.
What may have happened: The shaft for the damper is make of plastic, the motor has a metal probe. The tip of the shaft sometimes breaks, allowing the motor to rotate inside the plastic shaft. Some on this board have re-glued the plastic shaft together, then wound wire around it to reinforce it. Then the motor gets shoved back in and it works again.
Just remember, the motor thinks it knows what position the shaft is in and if you put the motor back when it thinks the damper is open, but is infact closed, you will get blinking lights and have to pull the motor again. Or the motor tries to turn the damper which will not move, and the motor burns up.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Thanks Klaus, I looked at it again last night. I only find 4 dampers; Recirc (beside blower motor), L & R Temp (they oppose each other, towards top of box)and a damper on the driver's side of box, that is dual action. It has a white cam wheel behind the motor & moves 2 flaps in the box via a 90 degree arm that follows in the cam wheel. From the passenger side of the box, I can see the other ends of both shafts, and they turn both directions when center control knob is tuned. This is EEC, so the damper setup is different than the one in the picture you sent me. I think I will remove the dash top this weekend & see if there is something blocking the defroster vents.?. Thanks again, Phil
PS. Klaus, If you are damning the IRS and high taxes (as any 'free' American should), show your support for Dr Ron Paul for President in 2008!

A year or so ago, there was a V70 air/heater box for sale on Ebay. The whole thing is one sealed unit, from the pics. Taking the dash off will not gain any access.
My garage is below freezing so I will not climb in the car to take a look at my V70. Those pics are for an 850 with ECC, sorry, I hope it wasn't confusing.

PS I voted democratic in the primaries. I have some special circumstances in my taxes this year and it is truly painful. Turbo Tax is giving me problems, I have found 3 bugs already! Aaaarrrrrrggggh.

Klaus

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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Well, my wife comes home today, says she heard a noise under the dash again. She tried the fan on high, works fine! I am glad, but also bummed because I never figured it out. Thanks for your concern and help, Phil

Well, you know it will come back at the most inopertune time to bite you on the butt.
The next time you "play" with it, remember the damper motors and the dampers cannot change. Ie, when you decide to pull a damper motor, take off the 3 screws and pull the box away from the housing about 1/16 inch and let go. If the damper turns the motor, then mark that position so the motor goes back onto the shaft in the same position. Just scribe it with a felt tip pen before removal. Then when you put it back on, use the scribe marks to get it on the shaft and then turn the motor/shaft to get the screws in place.

In order to R&R the evaporator, the HVAC unit must come out. That is a 10 hour job for most mechanics. One of the retired mechanics at our dealership can do it in 4 hours, and the other mechanics watching him just get their minds blown away! Lots of parts, even more screws, and he has it down to a science including where to place the removed parts inside of the car. He does remove both front seats first to give himself room.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)