Blower motor works but no air is coming out

LOB · Post by **LOB** » 04 Oct 2021, 03:20

This problem is intermittent but seems to occur when you need the ventilation the most (occurred yesterday driving 500 km in very foggy conditions forcing me to use paper towels every 30 seconds for 6 hours,...). I think the problem occurs gradually and not suddenly (but I am not sure). The blower motor runs at full speed but it sounds like the airflow is clogged somehow. I've read some posts about "damper motor" etc but the problems described are not identical to my issues. The car has ECC.

Post by **jreed** » 04 Oct 2021, 05:08

If I were in this situation, I would check to see if the ECC unit has stored any error codes and make a note of them if so. Then I would clear the error codes and see which codes are repeated. I'm guessing you've already checked the cabin filter is clean (or removed) so it can't block airflow.
Another approach would be to remove the glove compartment and observe the operation of the damper motor and the plastic arm that connects to the damper when you select defrost and recirculation modes to see if they are OK and working correctly.
You could also pull out the blower motor and make sure it's not plugged up with leaves or spider webs or something else than could reduce the airflow.

Post by **scot850** » 04 Oct 2021, 11:11

Following on from what jreed says, are you getting no air at any of the outlets or just not the vents to the windshield. I am trying to think why you would not get any air out of any of the outlets at all, as normally even if the cold air flap is not working if you set to cabin recycled air you should still get air form some of the outlets either to face level or floor vents when the fan is blowing.
The only reason you would possibly get none is if the A/C evaporator is totally blocked which could only happen if you have no cabin filter in place (850's were not fitted with one). If you don't have a filter you can pull the filter holder from a 97-99 V/S/XC70 and fit it to your 850 which allows you to fit a cabin filter.

Neil.

LOB · Post by **LOB** » 06 Oct 2021, 02:01

Thanks for your help! There is no air coming out of any of the vents. Recycling mode or not. And the problem comes and goes so I guess its neither a clogged air filter nor a blocker evaporator. Is ECC part of the Vol-FCR protocol ? (I didnt bring my Vol-Fcr laptop to my cabin) or do I need to make on of those led diode blink tool)? I recently replaced the blower motor because it made a lot of noise and the cabin filter is also new. I guess I have to remove the glove compartment and inspect.

Post by **misha** » 06 Oct 2021, 02:53

ECC is fully OBDII from s,v70 series.
850's ECC unfortunately still produce flash codes...so...VOL-FCR will not work here.

Post by **ZionXIX** » 06 Oct 2021, 07:31

So if you remove the glove box and lower knee bolster and panel. That will give you good access to remove the blower again. Take your cell phone and set it to record with the light on and send it into the blower motor housing to get a good look at the evaporator. I did this a few years ago and it was quite alarming. I couldn't belive the thick layer of crud on my evaporator. I had to use long hemostats guided by the phone to peel off as much junk as possible. I still don't think I got it all but I'm not ready to pull the dash to clean it out just yet.

Post by **scot850** » 06 Oct 2021, 14:35

If you have zero air coming out from any of the outlets (windshield/face/floor) then their has to be a blockage somewhere which is kind of stating the obvious.

I think the first step is as Zion has suggested. Checking if the evaporator has been blocked over the years. Clearly if the fan is working correctly, the air can only go one way.

There is a directional flap that can stick internally, but I would have expected air out of some of the vents, even if only the floor ones.

Neil.

Post by **abscate** » 06 Oct 2021, 19:52

If you pull the power resistor/ transistor pack you can view the evaporator directly.

All air for the HVAC system has to pass through the evap.

gamlemis · Post by **gamlemis** » 14 Aug 2024, 15:22

Can you describe what you mean by power resistor /transistor pack, where is this located and how to remove it??
I have exactly this problem with my volvo v70 and need to inspect the evaporator
Regards
Claus

Post by **scot850** » 14 Aug 2024, 15:38

Welcome!

Are you asking about your 2004 V70? If so you are in the wrong forum. This is for the older Volvos 2000 < years (P80 chassis)

Your 2004 V70 is a P2 chassis. I'm not as familiar with the heating system on those and if they have the resistor 'pack' variable resistor in the same way.

If you have a P80 let us know in this thread and one of us can explain where and how to access it.

Neil.