Blower motor verrrrry slow and then slows to a stop, flashing ECC

[wheelsup]

Hey

So last winter I noticed my fan quit blowing. I shut off car and repowered and everything has been Ok.

Today starting up I notice the blower motor is running kinda weak. On my drive home it just shuts off and the ECC starts flashing. De-power/re-powering does not bring it back.

Let car sit a few hours, blower does come back on but very weak and slowly dies.

The motor is newer-ish, an Amazon special. Maybe 5? years old

The blower motor does seem to respond to the speed slider, as in further right ramps it up, it just never gets very fast.

Pulled codes and have a long list,

1-2-6
1-3-4
1-3-5
2-1-1
2-3-2
2-3-3
3-1-1
3-1-2
3-1-3
3-1-5
4-1-5
4-1-8 (most concerning, No control signal to blower fan power stage)

Car is old, and dying a slow death, lots of other issues including a bumper that is falling off held on by a trailer hitch...just need car to provide air for a bit more...ac evap was replaced a few years ago...it works well just need the blower to run over these 90* days!!

Thoughts? I was going to try to hook up the blower to 12v directly but not sure how to go about doing so. I'm not an electrical engineer and electronic stuff is very foreign to me...

[JimBee]

The bearing near the brushes dries up and gets clotted with debris from the brushes. I've resurrected a couple that continue to work after several years, but I don't run them at max speed. You can pull it, get it on the work bench, set a couple of supports either side, then using a flat bar on both sides under the edge of the squirrel cage, work the motor out of the housing. I think there are two screws on the motor housing you need to remove. Then clean it all up, if you have air, blow out all the brush dust and drip some kroil or PB Blaster into the bearing, rotate it to work it in, then I think I got some white lithium grease into the bearing as well. Probably won't last forever, but you might get a couple more years out of it.
Or you can buy a new one from FCP.

[abscate]

Or you can buy a new one from FCP.

Even better, buy your previous one from FCP

[jreed]

I got a new motor and installed it in the blower about 6-7 years back. It has been working normally since then. It would be a good idea to replace the motor before it causes damage to the blower power stage.
There is more info in this chain:
viewtopic.php?t=19322&start=100#p244540

[DeadEric]

It sounds to me like you have bad windings in your blower motor. The copper wires wrapped around the spinny ma-thing that make it spin. Those wires are dipped in a resin so they don't actually touch. Heat, vibration, and age crack the resin and allows them to short out. As they heat up (with use) the cracks get bigger and the short more apparent. Allow them to cool, the cracks shrink and the short "goes away."

With a lab scope (very fast graphing multi meter) you can watch the amp draw from the fan and "see" it happen. Amp wave going along fine until the cracks get bigger and you get high spikes and low dips. The shorts slow the fan until it shorts completely and the fan stops altogether.

My guess would be, the ECC is monitoring the amperage? With the spikes and dips coming in, it thinks "fan too fast, nope, fan too slow, nope, fan... I don't know... blink the lights 4-1-8."

[wheelsup]

Ok I cleared codes and pulled them again this morning. Blower did turn on (about halfway to medium) for a few minutes, then died. Only repeat code is 4-1-8.

I found this typed up by Lee:

The 4-1-4 code won't keep the blower from operating but the 4-1-8 code will. Chances are it is a bad "power stage" which is a fancy name for the electronic climate unit's blower resistor. It really isn't a resistor at all but that is how many of the parts catalogs name it. You can't really test it beyond replacing it with a known good unit but what you can test is the blower itself. Unplug the large connector on the power stage that has the blue and black wires. Use a jumper wire to short the two wires together and the blower should run at full speed and it shouldn't make any bad bearing noises. If it is noisy (beyond just normal air noise), then, at a minimum, you need to lubricate the bearings on the blower and get it to operate without bearing noise before you replace the power stage. A bad blower will kill the new power stage quickly and the power stage is a pricey item.

I jumped the blue/black wires and blower blows full speed ahead. Absolutely no issues with blower at all. I plug the resistor back in and blower does not function.

So it seems that the resistor is the problem, thoughts?

[abscate]

Well done. Bad power stage. Junkyard best source.

[jreed]

Agreed. There may be a 1996 Volvo 850 in the local (Durham LKQ) junkyard (maybe because the photos and links are not working for that particular listing). If it is really there, it's probably a 50-50 chance to have an ECC system.

https://www.lkqpickyourpart.com/locatio ... 2/recents/

And there's at least one on eBay for about $50:
https://www.ebay.com/itm/VOLVO-850-BLOW ... 7517!US!-1

[wheelsup]

Agreed. There may be a 1996 Volvo 850 in the local (Durham LKQ) junkyard (maybe because the photos and links are not working for that particular listing). If it is really there, it's probably a 50-50 chance to have an ECC system.

https://www.lkqpickyourpart.com/locatio ... 2/recents/

And there's at least one on eBay for about $50:
https://www.ebay.com/itm/VOLVO-850-BLOW ... 7517!US!-1

Yeah I saw the eBay listing unfortunately my car is the earlier part #, that is for later models.

[wheelsup]

Got the part from FCP, blue box Volvo and I haven't felt that much air out of my vents in years. Just in time for summer!