Fluctuating electrical power?

454cid · Post by **454cid** » 19 Feb 2022, 11:56

Yesterday and today, I'm noticing I've got fluctuating electrical power. I first noticed it because I can hear the blower motor speeding up and slowing down. It did it the first few minutes after startup yesterday, on my way to work, and the same today when going out for coffee. Initially, I thought it was just a cold blower motor, but last night, it also did it with the car fully warm, as I pulled into my driveway, and the lights were also affected.

The battery is new, and connections at the battery should be fine. I don't know where the grounds are to inspect/clean them. The 850 OBDII app reports voltage of about 13.3x, while driving.

I intend to go back outside later, and check voltage at the battery with my Fluke, and hope I can catch it while the fluctuations are actually happening.

Any ideas what's going on?

Post by **scot850** » 19 Feb 2022, 13:50

When was your blower motor last replaced? The description you give is of a classic failure of the fan motor bearings as they start to bind up which will draw more power.

If the motor has been replaced recently then chances are that is not the issue. If you have not replaced it then I would look there after your electrical test. You may get lucky by lubricating the bearings with a light oil and it may work for a while but it is giving you a warning of failure coming.

If you notice the fan motor speeding up or slowing down as you accelerate and decelerate then that is definitely the issue.

Neil.

454cid · Post by **454cid** » 19 Feb 2022, 14:07

scot850 wrote: ↑19 Feb 2022, 13:50 When was your blower motor last replaced? The description you give is of a classic failure of the fan motor bearings as they start to bind up which will draw more power.

I've only had the car since early January, and I assume it's the original blower.... only 88K miles on the car.

If the motor has been replaced recently then chances are that is not the issue. If you have not replaced it then I would look there after your electrical test. You may get lucky by lubricating the bearings with a light oil and it may work for a while but it is giving you a warning of failure coming.

I have the glove box out already, after my jammed/locked door, and can see the blower. It looks buried. I guess I'll have to do a Youtube search on removal.

If you notice the fan motor speeding up or slowing down as you accelerate and decelerate then that is definitely the issue.

I think it's all been at idle, or very low speeds (in the neighborhood). It doesn't seem to last long enough to do much testing, at this point.

454cid · Post by **454cid** » 19 Feb 2022, 17:04

Ok went back outside and braved the cold... it's in the upper teens (Fahrenheit) today.

Voltage at the battery was 13.7x, with no visual/audible fluctuations. Then I went to do a few errands, and no unusual behavior at all, the whole trip.

Now, that I think about it. I recall a few weeks ago, hearing the blower motor whining a bit at stop lights. I think I'm going to go ahead and order one.

Any brand preferences other than OEM Volvo?.... way too expensive for a blower motor and IPD says they're back ordered anyway. For my truck, I buy 4-seasons. I tried TYC once, and it was junk.... vibrated. I've heard VDO aren't great either, but that was for Chevy. Given that VDO is a European brand, maybe their Euro offerings are much stronger? IPD carries TYC, which surprises me a bit, but maybe the same thing there.... Ok for Volvo, garbage for Chevy? I ordered the TYC blower motor for my truck since the TYC radiator I bought has been great.

Post by **scot850** » 19 Feb 2022, 17:26

With such low mileage I would not rush out and buy a replacement yet. The 850 does not have a cabin filter as standard and so leaves and assorted crap can get down in there.

I can't recall if you already did this, but if not, you can get a filter holder from a V/S70 and drop it in under the cover of the wiper motor and it will then allow you to use a cabin filter.

The motor is not unduly hard to remove but been a while since I did an 850. Can't recall if they have the knee protection bar on the passenger side. f so, it has 3 nuts that need to be removed and then it can be persuaded to come out. Then you can get access to the motor more easily. There are about 4 or 5 T25 Torx screws aound the perimeter and then it comes out wit a bit of discussion!

I would clean the fan blades and then oil the bearings and spin it before re-fitting.

Then try it and see if there is an improvement.

Check while you are in there the plastic arm for the cold air flap behind the fan motor has not broken between the servo motor and the flap. Also take the opportunity to clean as much filth out of the fan area and flap.

Neil.

454cid · Post by **454cid** » 19 Feb 2022, 18:38

scot850 wrote: ↑19 Feb 2022, 17:26 With such low mileage I would not rush out and buy a replacement yet. The 850 does not have a cabin filter as standard and so leaves and assorted crap can get down in there.

I can't recall if you already did this, but if not, you can get a filter holder from a V/S70 and drop it in under the cover of the wiper motor and it will then allow you to use a cabin filter.

Yes, I did install the filter, after purchasing the holder though ebay.

The motor is not unduly hard to remove but been a while since I did an 850. Can't recall if they have the knee protection bar on the passenger side. f so, it has 3 nuts that need to be removed and then it can be persuaded to come out. Then you can get access to the motor more easily. There are about 4 or 5 T25 Torx screws aound the perimeter and then it comes out wit a bit of discussion!

I have some sort of plastic piece that's got an SRS sticker on it.

I would clean the fan blades and then oil the bearings and spin it before re-fitting.

Then try it and see if there is an improvement.

I assumed oiling was quite temporary, and I really only wanted to mess with it once, especially in this weather, and doubly so it if doesn't improve anything. I'll consider it... I might be able to do it tomorrow.

Check while you are in there the plastic arm for the cold air flap behind the fan motor has not broken between the servo motor and the flap. Also take the opportunity to clean as much filth out of the fan area and flap.

It's broken.... it's no longer connected to the servo motor. I assume this is for the recirculate function? I'm not sure how to access this, even if I do have a replacement.

Post by **scot850** » 19 Feb 2022, 19:15

There is a little plastic arm about 3" long that fits over the arm of the flap and the other end over the servo motor arm. Tomorrow I will see if I can find one to show you.

The servo motor is easy to remove. There is a small Torx screw (T15?) if I recall at the top edge of the motor. Remove this and the motor should slide out toward you.

When fitting a replacement arm, use the cotrols on the ECC unit to close and open the flap so that you can make sure you fit the arm in the right place.

Neil.

Post by **scot850** » 19 Feb 2022, 19:32

Hopefully Okay to post this. The 'intermediate' arm is #18 on the drawing and the servo motor is just to the left of the motor.

V70 Climate Unit Parts.pdf: Heater system parts; (148.63 KiB) Downloaded 89 times

Been a long time since I swapped the motor out on an 850 and seem to recall a small level of complexity greater than the V/S70 due to the knee brace being in the way. Maybe I am confusing it with a 98 V70. Later cars don't have that.

V70 heater fan (1).pdf: Heater fan motor removal; (67.23 KiB) Downloaded 100 times

Hope this helps. If it is not ok to post this then please remove.

Neil.

Post by **scot850** » 19 Feb 2022, 19:57

Just searched through my pictures over the years and found this one:

: Cold air flap servo and intermediate arm; 20160831_123923.jpg (951.69 KiB) Viewed 1368 times

The arm is the black up and down arm in the upper center of the picture. You can see at the top of it the square silver drive from the servo motor. At the bottom the white part with the brass piece in the center is the arm to the cold are flap. It is fiddly and the arm has to be fitted in a particular way.

The screw for the servo motor is just above the arm and we are viewing it side on with the hear of the screw to the left.

Neil.

454cid · Post by **454cid** » 20 Feb 2022, 01:04

The arm on mine is white and I believe snapped at the square hole, so it just flops around now. It's 14 in the PDF you linked, but 18 in the stuff online from the Volvo parts site, they must have changed the numbers in later revisions. I get 6808653, which seems to be available from Ipd, and FCP, but hard to find with their own systems. Google found them first.

So I guess it just slides over and floats on the square actuator shaft, but how does it attach on the other side? ...to the push rod or "link arm" as Volvo calls it? There's also a "bushing" in there, but it seems to be a retainer of some sort.... FCP has it: 9137233. It's not clear to me how that fits together.

I'll see if I can get in there with my phone/camera and get an up close picture of what's there on my car, as far as that broken arm.