Volvo 850, 1995, ECC damper motor problems

Flow · Post by **Flow** » 05 Oct 2017, 15:33

Hello, from couple of months i have a problem with ECC damper motors, the air comes only from the front, when i switch to floor or defrost nothing happen, Temp adjustment and fan speed works good
There is two error codes 2-3-1 and 2-3-3.
All damper motors working when i plug them to 9v battery.
I've replaced blower resistor whole electric bundle from control panel to damper motors, interior temp sensor e.t.c. tried 4 different control panels and nothing has change...
Maybe someone had a similar problem and he could advise me something.

Regards and I'm sorry for my English.

Post by **abscate** » 05 Oct 2017, 20:35

Dzien Dobry!!

If the motors test out, then probably the control unit is causing a problem

Flow · Post by **Flow** » 06 Oct 2017, 02:53

I have 4 control units each of them works the same.
The temp knobs, fan speed, recirculation works but the floor, defrost motors doesn't.

Post by **jreed** » 06 Oct 2017, 05:17

When I looked up the meaning of the 231 and 233 codes I saw that they both have to do with the position sensor inside the damper motor. In my experience this means the dampers need to be opened up and the carbon resistance tracks inside cleaned off. They get covered with grease and stop working after a while.

231 Ventilation damper motor position sensor open circuit or shorted to 12 volts
233 Floor/defrost damper motor position sensor open circuit or shorted to 12 volts

Flow · Post by **Flow** » 06 Oct 2017, 11:17

I think the problem its not with motors, when i'm take passenger side temp damper motor (which works good) and swap it with defrost damper motor, it's still the same situation, temp motor works, defrost not.

Post by **scot850** » 06 Oct 2017, 16:20

Check the actual flaps are moving. I had an 850 where the flaps had melted to the internals of the air box and it would not turn. Also check the sleeves at the ends of the flap arms are not cracked. That is a common issue. You can often fix the slit using a small clamp or sometimes a zip-tie.

Neil.

Flow · Post by **Flow** » 07 Oct 2017, 10:34

Flaps, shafts e.t.c everything is ok, i can easily turn them by hand when i unscrew the motors.

Post by **sleddriver** » 07 Oct 2017, 11:28

Flow wrote: ↑07 Oct 2017, 10:34 Flaps, shafts e.t.c everything is ok, i can easily turn them by hand when i unscrew the motors.

I wrote up my experience a few years back, of diagnosing my system. Search for it under my name.

Post by **scot850** » 07 Oct 2017, 11:45

Check the ends of the shafts where the motors sit into are not cracked. Have you calibrated the motors to ensure they are in the correct positions for open and close?

If the motors move normally when removed from the flaps when the ECC position is changed then the ECC unit is good. Check when you re-fit the motors they are at rest in the correct position for open/close when activated.

Neil.